MIG Weld Equipment &
Pulsed MIG Weld
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refresh each page before you start.
If you want to read how pulsed MIG caused major weld cracks
on Ford truck
axles, continue to pulsed
section 2. (bottom of page).
Aisan and European mfg. management love to waste money on
useless, pulsed MIG weld equipment, electronic bells & whistles.
Large Aisan, European and North American mfg companies have for decades payed a huge price for weld process management ignorance.
It's especially ironic that in 2014, in Asia, where weld labor costs are typically low, that you will find the majority of large weld - fabrication companies are demanding very expensive Chinese made pulsed MIG equipment. The sopisticated electronic, Pulsed MIG equipment typically costs $6,000 to $15,000. It's a weld reality that In 2014, as it's been for at least 25 years, most of the weld shop managers who make the Pulsed MIG equipment purchase decisions, are rarely aware that the sophisticated, pulsed equipment, will in contrast to a $3,000 to $4000, well made, regular CV, MIG power source, will result in the following:
PLEASE REMEMBER THAT THE PRIME PURPOSE OF ANY WELD IS TO
FULLY FUSE TWO OR MORE METAL COMPONENTS TOGETHER.
The costly, pulsed MIG units will on most welded parts > 2.5 mm, produce welds with less weld fusion and welds with more porosity. The reason for the pulsed MIG weld fusion and porosity concerns is a simple one. Those pulsed MIG welds will typically spends 50% of their arc on time, with a pulsed back ground current of less than 100 amps.
In contrast to the traditional, open arc, Spray weld from a low cost Constant Voltage MIG unit, It's logical that any pulsed weld will put in less weld energy. For those that want proof, it takes five minutes. First make sure your weld personnel are trained to set optimum MIG spray settings with a CV MIG power source. (if they can't answer the MIG weld questions at the top of the page, they are not trained). On clean (no mill scale 3/8 - 1/2 steel test plates, have the welders produce a single pass, 1/4, (6 mm), horizontal, spray fillet weld. Section both the spray and pulsed welds in the middle, and examine the weld fusion and porosity in both the weld cross sections..
[b] A key characteristic of a Pulsed MIG weld, is with the "lower open arc weld energy potential" than a conventional MIG spray weld,the pulsed mode will benefit specific, limited, manual, heat sensitive applications such as weld cladding (require low weld dilution) and thin heat sensitive, < 3 mm aluminum welds. Pulsed MIG benefits are also attained with automated all position, pipe welds, in which the MIG wire stickout, the weld travel speeds, and the weld weaves are controlled. The weld shop reality however is that 99% of all manual MIG welds, will with low cost argon 2 - 20% CO2 mixes, achieve the highest posssible weld quality, (with minimal spatter) at the lowest possible weld costs. However the MIG spray welds, will rarely be attained by weld personnel that play around with their weld controls. To optimize MIG - FCA weld quality - productivity has never required sophisticated MIG equipment or three part gas mixes, theses welds simply need to be made by individuals who have recieved training in MIG - FCA weld process controls and best weld practices.
MOST WELD SALES REPS, EITHER DON'T KNOW, OR DON'T WANT THEIR CUSTOMERS TO KNOW THAT THE HIGHEST MIG WELD QUALITY AND PRODUCTIVITY CAN BE MADE BY LOW COST MIG EQUIPMENT AND GAS MIXES.
As the weld parameters can change with every different Pulsed MIG power source, weld procedure qualification typically means little with the pulsed MIG process.
By the way, I know that few companies have given consideration to the fact that each new pulsed MIG unit bought into the plant should typically require a new, costly, weld re-qualification of existing weld procedures. Again the reasons for the re-qualification of the welds, is every new model of pulsed MIG equipment will typically will have major electronic changes, and for a given wire feed rate the pulsed output changes could dramatically impact the weld energy produced. The bottom line is this. If for example your company spent thousands of dollars on a pulsed MIG weld application qualification 5 yrs ago, and then they purchase that new pulsed MIG equipment today they should take a look at requirements of the weld codes that typically don't allow changes in essential weld variables.
I predict that not worrying about weld fusion changes from pulsed equipment changes and not re-qualifying the pulsed welds with that new pulsed equipment, is just another one of those weld shop concerns that one day will have dramatic weld failure, and costly weld cost liability consequences for some companies.
[c] That new, overpriced pulsed MIG weld equipment will in many instances rarely get through it's short warranty period without circuit board issues that will likely impact your companies weld quality - productivity. When the pulsed unit does require repairs, expect to pay thousands of dollars, and pray it wont take more than a month or two to repair. Please also be aware that your organization added to the pulsed equipment longevity and durability concerns when the pulsed equipment purchased was made in China. With Chinese pulsed MIG units I believe you should expect extensive costly repair and weld performance and weld quality issues.
In contrast, that low cost, regular, USA made MIG equipment should typically be in weld shop service, without requiring repairs, for 10 to 25 years. Also note most electricians should have the ability to repair regular CV equipment at low costs.
I have evaluated global pulsed MIG equipment for approx three decades. I have written over 100 pages in, "My Management - Engineers Guide To MIG" book, on what's wrong with the Pulsed MIG process and my Process Control training programs, also tell you what's wrong with the pulsed equipment, and at the same time how to get the best out of a pulsed MIG unit. The reality is for the majority of ferrous and none ferrous weld applications, will be the only companies that benefit from pulsed MIG equipment sales, are the companies that make and sell pulsed MIG units.
The reason managers and engineers around the globe buy into the pulsed hype is the too common weld shop reliance on salesmanship for MIG equipment advice, and of course also the general weld process control - best practices ignorance. So instead of wasting many thousands of dollar in the purchase of that pulsed MIG unit, I would recommend the weld shop purchase of a well made USA Miller - Lincoln. CV $3000 - $4000 350 - 450 CV MIG power source. If selecting European CV equipment consider ESAB CV units. To get the best out of this equipment I would advice you to spend a whopping $400 on my MIG or Flux Cored Weld Process Controls - Best Weld Practices resources.
2013: PLEASE NOTE: PULSED MIG IS A DIFFERENT WELD PROCESS WHEN IT ATTAINS THE CONTROLLED WELD BENEFITS FROM WELD AUTOMATION: It's important that the weld industry understands the reasons why the pulsed MIG process when used with automation such as mechanized pipe units or with robots. With automation controls, pulsed MIG can produce superior vertical up weld quality than the welds made with conventional CV equipment.
The conventional, open arc, MIG spray transfer welds provide high weld energy and the welds are usually too fluid to control for most vertical up weld applications. In contrast the pulsed mode provides lower weld energy open arc welds that solidify at a more rapid rate than a spray weld. The faster freeze, lower energy pulsed welds as many in the oil and energy industries are aware, will often on manual vertical up pipe applications create welds with lack of weld fusion.
When a high deposition, moderate energy process such as Pulsed MIG is used for all position, manual welds, the welds are made at much faster weld speeds than the TIG - SMAW and sometimes the FCAW process. The faster pulsed MIG weld speeds with the inconstant manual weld weave techniques and inconsistent weld speeds will often result in lack of fusion and porosity defects
In contrast when we see pulsed MIG used with costly, mechanized, pipe applications, you can apply controls to the process so the welds can be made to meet the pipe weld code requirements
When dealing with mechanized, pulsed MIG pipe weld equipment as found with oil industry pipe applications, you will often find multi-gun units with sophisticated pulsed weld equipment and controls. The automated, pulsed equipment will provide dedicated pulsed MIG weld programs suited to the unique requirements necessary for the pipe weld roots, fill and cap passes. The message here is two fold.  All position mechanized pipe welds are a fraction of one percent of all MIG welds.  Don't expect the weld results you will attain from the automated pulsed MIG process, with the weld quality results you will achieve from the manual pulsed MIG process
SINCE IT'S INTRODUCTION IN THE EIGHTIES, I HAVE BEEN EVALUATING PULSED MIG EQUIPMENT FROM GLOBAL MIG EQUIPMENT MFGs . IN MY WELD TESTS OVER THE THREE DECADES, I SAW THAT THE ELECTRONIC DIFFERENCES AND RESULTING PULSED ARC CHARACTERISTICS BETWEEN ONE PULSED MIG EQUIPMENT MANUFACTURER AND ANOTHER MANUFACTURER, WERE EXTENSIVE.
In 2014 little has changed.
BACK TO THE REAL WORLD: For five plus decades, as it still is in 2014, the low cost < $4000. well designed, USA (and some European) built, constant voltage, CV, MIG equipment, has provided a moderate slope output which for a given wire feed setting will provide the ideal weld current for all weld applications.
WHY THE CONCERN FOR MIG PROCEDURES? THINK ABOUT THE MILLIONS OF EXISTING, CV MIG WELD PROCEDURES PRODUCED OVER THE LAST FIVE DECADES, THOSE PROCEDURES ARE USUALLY TUCKED AWAY IN A FILE IN THE QA MANAGERS OFFICE. WHEN YOU USE PULSED MIG, YOUR ORGANIZATION WILL HAVE THE HIGH COSTS ASSOCIATED WITH WELD PROCEDURE REQUALIFICATION. ALSO NOTE THAT WHEN YOU CHANGE THAT PULSED EQUIPMENT FROM ONE YEAR TO THE NEXT, THE WELD OUT PUT WILL LIKELY BE VERY DIFFERENT, AND BY RIGHTS, YOU SHOULD AGAIN SPEND THOUSANDS OF DOLLARS ON REQUALIFYING THE WELDS.
WHAT ABOUT FLUX CORED WELDS ON THE PULSED EQUIPMENT?
Give some consideration to the fact that all flux core wires were developed with traditional CV MIG equipment and produced their weld teat results with . the weld energy that the CV equipment delivers for a speciic recommended flux cored wire feed setting. If you use Pulsed MIG equipment for the flux cored wires, and switch the pulsed equipment to it's CV MIG mode, as the slope on the pulsed MIG equipment is typically steeper than regular CV equipement, the end result is the pulsed unit will typically deliver less weld current. Those faster freeze pulsed MIG flux cored welds may generate weld fusion, porosity or slag concerns.
THE BOTTOM LINE. FOR DECADES DIFFERENT MIG EQUIPMENT MFGS HAVE PROVIDED 300 - 450 AMP CV, MIG POWER SOURCES AND THEY TYPICALLY HAVE HAD SIMILAR SLOPES AND THEREFORE CV EQUIPMENT HAS PROVIDED SIMILAR WELD PERFORMANCE.
The MILLER DELTA WELD EQUIP, AND IN THE OLD DAYS, THE LINDE SVI EQUIPMENT, WAS SIMPLY THE BEST PERFORMING EQUIPMENT
WITH THE LOW COST, CV EQUIPMENT, LIFE FOR THE WELD SHOP SHOULD HAVE BEEN SIMPLE, THAT IS IF MANAGEMENT HAD PROVIDED MIG PROCESS CONTROL TRAINING. WITH THE TWO SIMPLE CONTROLS, THE DURABLE, LOW COST, CV EQUIPMENT COULD PROVIDE SHORT CIRCUIT, GLOBULAR OR SPRAY TRANSFER THAT WOULD PROVIDE LOW,- MEDIUM AND - HIGH ENERGY MIG WELDS SUITED TO 99% OF WELD APPICATIONS.
Ref pulsed MIG pipe welding concens:
5.2.3 states that the Pulsed Gas Metal Arc Welding (GMAW-P) process may be used for
any material thickness. However whenever the welding system is changed or the settings
on existing equipment are "significantly altered", the fabricator should
verify the reesulting weld properties. The extent of verification or testing should be as agreed
between the purchaser and fabricator.
Response from Ed's MIG WELD
REALITY. In contrast to the traditiona, two control, MIG or flux cored weld process,
there are many weld essential variables that can be readily changed with the pulsed MIG
mode. While the API code engineers warn against a "SIGNIFICANT change in a pulsed
settings", the real world weld decision maker needs to be aware that an insignificant parameter change with the highly sensitive pulsed MIG mode, will have a significant influence on the weld fusion, and that weld fusion will in most instances will be marginal or lacking.
While on the subject of pulsed MIG, the API code does not discuss the mechanized versus
manual pulsed welding inconsistencies. When a code body stipulates that a fusion sensitive
process is OK for any pipe thickness, the code is sending the message that this
process is acceptable for both manual and mechanized welds.
With automated pulsed MIG pipe line welds, electronic power source features such as volt or current energy spikes can be applied to the weld weave dwell times. These increased energy spikes will impprove the pipe side wall weld fusion. Also the controlled pulsed MIG weld speeds, controlled mechanized weld weaves and constant wire stick out will have a lot to do with success of the mechanized pulsed
MIG process when used for pipe line welds.
Without the automated weld controls, for three decades the manual pulsed MIG weld process has proven that the attainment of 100% X-Ray all position manual pipe weld quality is a challenge, and this is a challenge that weld shops in 2013 do not have to face when they can use the far superior TiP TiG process.
Pipes and weld process choices..
Ten years ago SMAW (STICK) and Flux Cored were most common processes for large pipe welds.
PULSED MIG AND PIPE PROJECTS: Large pipe projects especially in the oil industry will today often use a mechanized, multi-torch, pulsed MIG unit for the pipe welds. The pulsed MIG equipment may or may not have a level of electronic sophistication way beyond that available in standard pulsed equipment sold for manual pulsed weld applications.
For mechanized pipe root welds, either the MIG CMT - STT - RMD modes will typically be selected, and for the pipe fill - cap pass welds, the more conventional pulse mode will be selected. Apart from the dedicated pulsed programs for the pipe fill and cap passes with the pulsed equipment, you will also find the pulsed equipment and controls may enable unique pipe weld attributes. For example the equipment may have the capability to provide a current or volt spike during the weld dwell time in the weld weave cycle.
Vee and J groove pipe welds have simple weld requirements. Moderate MIG weld energy is required across the hot groove weld surface, and higher weld energy with dwell times is beneficial when applied to the Vee or J groove side walls, (the thicker the pipe the higher the side wall energy required). The weave dwell energy spike from this unique pulsed process can overcome the common pulsed MIG side wall (lack of weld fusion) weld issues, (a sophistication at this time not possible with manual pulsed pipe applications). Most large automated pipe applications will enable multi-MIG guns which also add more weld heat into the groove welds again improving the weld fusion potential. Mechanized pipe welds also provide Constant MIG Wire Stick Out and Constant Weld Travel Rates which enable improved weld process control and bring a weld quality uniformity and consistency to the automated weld that again is not be possible with the manual pulsed MIG pipe welds.
2103: LETS GET BACK TO WELD REALITY. AFTER TWENTY FIVE YEARS OF PAINFUL, MANUAL PULSED MIG EQUIPMENT EVOLUTION, DEPENDING ON WHO'S PULSED MIG EQUIPMENT WAS PURCHASED, MANY WELD SHOPS WILL HAVE PROCESS THAT CAN CAUSE MORE WELD ISSUES THAN IT RESOLVES:
In 2013 we now have in North America, a
few pulsed MIG power sources that actually work in a
consistent manner and may possibly get through their
36 month warranty period without circuit board or electronic
issues. The question that needs to be asked when selecting pulsed for manual steel and alloy steel applications was the purchase of this sensitive process justified in contrast to the lower cost CV MIG equipment.
There are obvious weld benefits attained for pulsed MIG aluminum welds (alum require less weld energy than spray) and for specific MIG stainless welds that benefit from an open arc mode that enables lower weld heat than spray to possibly reduce distortion. Remember the key benefit of a MIG weld mode is the ability to provide consistent weld fusion, and on most weld applications, spray transfer will provide superior weld fusion than pulsed. Alway remember that Pulsed MIG is a process which spends 50% of its time at a back ground weld current of usually less than 100 amps. The pulsed process is also a good subsitute (in most instances not necessary) for the gague welds that are typically welded with short circuit, or when welding alloys that have poor weld transfer characteristics with conventional short circuit or spray transfer.
As many pipe welds shops have found out, ypically when pulsed MIG is used for "manual" pipe welds that require "100% X-Rays", a combination of variables and factors will come together and lack of weld fusion may become a common weld defect. In contrast to SMAW and TIG used for pipe welds, each hour pulsed MIG will typically provides at least 10 times more weld and is therefore considered a high deposition process. When it comes to MIG weld defects that high weld deposition rate takes a large part of the blame.
Fig. The outside appearence was irrelevant.
If you provide what you think is an optimum pulsed MIG fillet weld on 3/8 (9.6mm) steel plates and then provide a macro section of the fillet weld, you will often see either marginal or lack of side wall weld fusion. After the macro weld evaluation you may come away with the impression that with pulsed MIG, you have a weld process that provides a poor ratio of weld energy to the weld deposition - mass and the weld speeds provided. Also with manual pulsed MIG welds the weld energy is influenced and the weld transfer is disrupted by the manual wire stick out variations and the many different weld techniques that each welder brings to the pulsed weld.
THE RATIO OF THE WELD ENERGY DELIVERED AND THE WELD MASS AND WELD SPEEDS THAT RESULT IS ALSO AN ISSUE WITH MIG SPRAY TRANSFER, HOWEVER THE WELD SHOP NEEDS TO REMEMBER THAT WITH PULSED MIG THE WELD SPENDS 50% OF IT'S TIME WITH A BACK GROUND CURRENT < 100 AMPS.
WELD PROCESS EXPERTISE CAN OFTEN OVERCOME POOR WELD EQUIPMENT TECHNOLOGY.
IN THE 1990s, I SET OPTIMUM PULSED WELDS ON THE WORLD'S MOST COMPLICATED ROBOT WELDS.
Fig.. The most complex welds are small pipe and tubes, that have difficult acces and 100% X-Ray
THE EASIEST PIPE WELDS TO MAKE ARE LARGE DIAMETER PIPES (EASIER TO FOLLOW THE RADIUS AND MORE TIME TO REACT). IN CONTRAST THE MOST COMPLEX PIPE WELDS ARE SMALL DIAMETER PIPES AND TUBES.
I remember in the 1990's, when the management team at one of the world's largest engineering companies decided to purchase a seven axis robot to weld it's boiler tubes to headers. The above picture is not the parts welded but similar and the tubers were slightly larger. The boiler head pipes were approx. 8 - 10 diameter, typically 20 to 40 feet long with the 2 - 3 inch diameter thinner wall tubes. The robot traversed on a track placed on the other side of the header. These complex ASME welds were typically carried out by the highest skilled manual TIG welders. I won't go into why the management should not have selected a costly robot for these welds, however I would like to tell you about the pulsed MIG welds I produced on this robot application.
For each boiler tube to head weld, two robot pulsed MIG weld layers were required to fill the grooves and produce the fillet around the header. The pulsed MIG welds had to pass 100 X-Ray as per the ASME requirements. As the robot could not go 360 degrees around the tubes each of the two weld layers was made with four passes so four weld start - stops was required for one layer, with a total of 8 start - stops for the completed 2 weld layers, by the way no grinding or human involvement was allowed for the weld layers.
THE PULSED MIG TECHNOLOGY WAS 10 YEARS OLD. THE ELECTRONICS IN THE PULSED EQUIP WERE POOR AND AND NOT UP TO THE TASK. SO I USED MY PROCESS CONTROL EXPERTISE TO ACHIEVE THE ASME PIPE WELD QUALITY:
Can you remember how poor computers were in the early 1990s? well I want you to try and imagine how bad the global electronic pulsed MIG equipment was at that time. I had a sophisticated robot attached to to an inconsistent - erratic pulsed power source and had to provide optimum weld quality with vertical up, tube to header welds on two very different part thicknesses. In those small circular welds we had 8 weld starts and 8 weld stops that required perfect weld tie-ins to get past the X-Rays.
REMEMBER WITH SMALL DIAMETER MIG WELDED APPLICATIONS AND WITH SMALL WELD LENGTHS, THE WELD ARC ON TIMES MAY BE MEASURED IN A FEW SECONDS AND YOU NEED TO RELY ON THE WELD EQUIPMENT AND CONTROLS TO GO FROM WELD START DATA TO THE WELD DATA AND TO THE WELD END DATA IN THOSE FEW SECONDS. THE REALITY IS 2013 FEW AUTOMATED UNITS ARE GOOD AT PROVIDING THIS FUNCTION, SO IMAGINE WHAT WE HAD TO WORK WITH IN THE 1990s.
All the tube to header welds needed was one poor weld tie or lack of fusion and the ASME, 100% X-Rays would mark the weld as a failure. I used all my MIG weld process control expertise to make these robot welds work and produce an eight hour weld quality with better weld productivity and no more weld rework than that attained from the manual TIG welders. How did i solve the weld fusion - weld tie in issues?. For the side wall weld fusion I used robot weave dwell times and kept the pulsed MIG weld mass as thin as possible. For the weld start - stop tie-ins, with the robot weld end - start data, I used low wire feed than the weld with higher weld voltage which with carefullly selected dwell time provided good tie ins, (creating a dwell time energy spike) which is similar to what is today, >17 years later being used by oil companies and there much more conntrolled, sophisticated, pulsed MIG equipment. I trained a technician to make those robot welds and soon after he quit and I believe the robot was eventually put out to pasture. In 2013 the tube to header welds would still be a high risk robot application especially when you can now do these welds with the easy to use TiP TiG process. www.tiptigusa.com.
1990s.. Ed (left - right) comparing MIG short circuit versus the
STT and RMD MIG weld modes on Imperial oil, nat gas pipe.
WELD CODES, CONFUSION OR INADEQUATE INFOMATION.
it comes to MIG and flux cored welding, rather than providing weld process resolutions,
most codes relevant to pipe welding will provide inadequate information or the information they provide simply adds to the global weld process myths and confusion.
decision makers often look codes such as AWS - API and - ASME to provide practical, pipe welding
advice and recommendations. Those individuals that that put all their faith in the codes that are governing the specific weld applications they are working on, need to be aware of a little weld reality, The weld information in these codes has too frequently been written and influenced by
code committee individuals who lacked MIG / Flux Cored weld process controls & best practices / application expertise.
AFTER THE INTRODUCTION OF THE "MIG PROCESS",
AND 35 YEARS AFTER
THE INTRODUCTION OF FLUX CORED ELECTRODES, THE PRIMARY WELD CODES WHEN ADVISING ON THESE PROCESSES STILL CREATE CONFUSION AND TOO MANY QUESTIONS.
5.2.3 Pulsed Gas Metal Arc Welding (GMAW-P. This code states that the pulsed process may be used for
any material thickness and whenever the welding system is changed or the settings
on existing equipment are "significantly altered"then the fabricator should
verify the weld properties. The extent of verification or testing should be as agreed
between the purchaser and fabricator.
In a world in which engineering standards should apply, what the hell does significantly altered mean. In contrast to the traditionaL, two control, MIG or flux cored weld process,
there are many weld essential variables that can be readily changed when utilizing the pulsed MIG
mode. While the API code warns against a "SIGNIFICANT CHANGE" in a pulsed
settings", the real world weld decision maker needs to be aware that an insignificant, small parameter change with the highly sensitive, manual pulsed MIG mode, can have a significant influence on the weld fusion attained.
While the code bodies in 2013 have very little negative to say about pulsed MIG process, for those of you with grey hair, you may remember that these same codes typically either did not allow regular MIG or the code weld specifications made incorrect recommendations or negative comments on the use of MIG. For example, for five decades, the MIG short circuit process has been treated like a leper, yet the weld reality was and still is in 2013, the Short Circuit mode is the best weld transfer mode for carbon steel, "rotated" pipe, open root welds.
Most of the pipe shops which were embedded with the SMAW and TIG process would typically not consider using the MIG spray transfer mode for rotated pipe welds, yet the reality has been that MIG spray transfer on the rotated pipe applications should provide superior weld fusion and less porosity than any pulsed MIG transfer.
THE POOR PULSED MIG WELD MASS TO WELD ENERGY RATIO:
What most weld decision makers and QA personnel are not aware, is that there is on most all position, pulsed MIG pipe weld applications thicker than 6mm, a poor ratio between the moderate pulsed MIG weld energy attained, (influenced by peak to low back ground current changes) and the high weld deposition rates that typically result. The healthy pulsed MIG weld deposition rates push the high weld speeds, (faster weld speeds don't help weld fusion) along with the resulting large weld mass (larger weld mass creates a hinderance to the weld energy produced).
For those of you moving aggressively forward with the manual pulsed MIG process for your all position pipe welds, do not be surprised even when using the highest manual welder skills, when you X-Ray those sluggish stainless or nickel alloys to find lack of fusion.
YOUR LOCAL SALES REP WONT TELL YOU THIS BECAUSE THEY ARE NOT AWARE OF IT. OPTIMUM PULSED MIG WELD FUSION WITH MANUAL WELDS WILL OFTEN BE CONSIDERED MARGINAL, AND MARGINAL WELD FUSION WILL BE MADE WORSE BY THE MANY PROCESS AND HUMAN VARIABLES THAT INFLUENCE THOSE MANUAL PULSED MIG WELDS.
THE CODE RULES SHOULD CHANGE WITH AUTOMATED PULSED MIG WELDS:
I am not aware of any code that discusses the mechanized versus
manual pulsed welding differences and the weld quality consequences of those differences. When a code body puts it's stamp of approval on a weld process such as Pulsed MIG, the code is sending the message that this
is process that's acceptable for both manual and mechanized pipe welds.
With automated pulsed MIG pipe line welds in which the use of multi-MIG guns is typical, electronic MIG power source features such as volt or current energy spikes can be applied to the weld weave dwell times. These controlled, increased weld energy spikes will improve the 5G pipe side wall weld fusion. Also the controlled pulsed MIG weld speed, the controlled, mechanized weld weaves and the constant wire stick out. are the automated features that will have a lot to do with success of the mechanized pulsed
MIG process when used for pipe line welds. Take away these important controls and as it's been for three plus decades the manual pulsed MIG process has proven that the attainment of 100% X-Ray all position pipe weld quality is a challenge. By the way this is a challenge that weld shops in 2013 do not have to face when they can use the far superior TiP TiG manual or automated weld process.
API. 5.2.2 Short Circuiting
Gas Metal Arc Welding (GMAW-S). The use of GMAW-S shall be limited to the following
 For vertical welding, the root pass and second
pass progression for a material of any thickness may be either uphill or downhill.
Ed's response. There is no logic in using MIG short circuit, with the vertical up position on any weld application. Just as there is no logic in this cold process being used for the second pass which from a weld fusion potential is the most sensitive part of any pipe weld..
The fill and cap pass for butt or fillet welds may be welded with the short circuit
process, provided the thickness of any member does not exceed 3/8 in. (9.5 mm)
and vertical welding is performed with uphill progression.
Ed's response. Watch out for lack of weld fusion with the short circuit process welding vert up on any steel parts > 1/8 (> 3 mm0..
Ed testing both the short circuit and STT process
for Imperial Oil. Weld focus at the difficult 5 to 7 o'clock
LETS GET BACK TO 2013 AND MANUAL PULSED MIG WELDS. IT'S A SIMPLE FACT THAT IN AN INDUSTRY IN WHICH PLAYING AROUND WITH TWO SIMPLE MIG CONTROLS IS THE NORM, YOU WILL TOO FREQUENTLY FIND THAT WELD SALESMANSHIP OFTEN PLAYS A LARGE ROLL IN THE PULSED EQUIPMENT PURCHASE,
A point managers need to address when purchasing pulsed MIG equipment. Was the person who selected the pulsed MIG equipment in full control of the traditional MIG equipment that's been around for decades. If they were in control of the lower cost CV MIG equipment, they should not have been having MIG weld quality - productivity issues with most steels and alloy welds.
IT'S 2103: PLEASE NOTE THIS SITE HAS BEEN HERE SINCE 1997, CONSIDER IT A BLOG, A HISTORY OF WELD ISSUES AND EXAMINE HOW WELD PROCESS AND EQUIPMENT PROBLEMS OF THE PAST ARE SO OFTEN RELEVANT TODAY. ENJOY REGARDS ED CRAIG. www.weldreality.com.
As a result of more than two decades of
poor performing, erratic pulsed MIG equipment, the global
MIG weld industry has flushed down the drain, hundreds of millions of dollars in unnecessary weld weld equipment - weld quality and productivity costs. The costs were
 unnecessary robot - manual weld part rejects,
 unnecessary robot - manual weld rework,
 unnecessary robot down time,
 operating with lower weld deposition rates (higher labor
costs) than that which could have been attained from conventional MIG spray transfer,
 unnecessary costs for the the robot - manual pulsed
MIG weld equipment,
 unnecessary high costs for the pulsed MIG equipment repairs.
IN THE 25 YEARS OF PULSED MIG PROCESS DEVELOPMENT, I DO
NOT KNOW OF ONE PULSED POWER SOURCE THAT WAS RECALLED DUE
TO PULSED EQUIPMENT OR WELD ISSUES. THIS PATHETIC
SITUATION IS A REFLECTION |
OF THE GENERAL MIG PROCESS MANAGEMENT APATHY
THAT EXISTS IN GLOBAL WELD SHOPS?
Of course weld equipment manufacturers like ESAB, Lincoln,
Miller, Hobart and Panasonic should always act in a responsible manner and recalled the pulsed MIG equipment that they knew had electronic issues. However
if their customer (weld shops) were not complaining, (they lacked the expertise to correctly evaluate MIG equipment), then why would the equipment manufacturers bother with a recall?
WELDING MOST COMMON STEEL -
STAINLESS APPLICATIONS, A QUALIFIED WELD DECISION MAKER,
WITH AN UNDERSTANDING OF MIG WELD PROCESS CONTROLS WOULD NOT
SEEK THE ADVICE OF A SALES REP AND PURCHASE MIG EQUIPMENT
THAT BRINGS NO REAL WORLD WELD QUALITY OR PRODUCTIVITY IMPROVEMENTS.
A weld reality for steel welds: The majority of the pulsed MIG equipment purchased from the early nineteen eighties to 2013, has been selected and purchased by individuals who lacked MIG weld process control expertise necessary to optimize the much lower cost. traditional, CV, MIG equipment.
Note: If you want the ultimate books and MIG and flux
cored weld best practices and process
control self teaching or training resources, click
2008: Engineers, managers,
technicians and supervisors
who for decades have a difficult time
the simple, two control
MIG power equipment, are now talking about controlling MIG equipment with useless "wave
> 2008: The
electronic pulsed MIG equipment that has been developed for
more than the last two decades for carbon steel and
stainless welds is finally delivering a few real world weld
benefits, however before you waste thousands of dollars on
a pulsed MIG power source check out the following pulsed MIG information
from equipment - process evaluations from
IN CONTRAST TO THE LOW COST, TRADITIONAL, DURABLE MIG EQUIPMENT
THAT CAN PROVIDE OPTIMUM SHORT CIRCUIT
AND SPRAY TRANSFER WELDS;
 PULSED AND ALUMINUM MIG WELDS: Pulsed MIG provides benefits welding < 4 mm aluminum parts. When used on alum part > 4, mm, in contrast to spray transfer, pulsed MIG may produce inferior aluminum weld fusion and produce welds with more porosity.
 PULSED AND GAGE STEELS MIG WELDS: Pulsed MIG can provide limited weld benefits for steel gage parts, (20 to 10 gage) however the weld benefits are so limited there is no justification for the purchase of the pulsed MIG equipment.
 PULSED BETWEEN GAGE AND THE THICKER METALS: When manual welding 2 to 4 mm Carbon steels and Low Alloy steels, with these welds when used with automation and robots, the pulsed MIG process can provide slightly higher weld deposition rates that enable faster weld speeds. (be aware those speeds cannot be achieved with manual welds).
 PULSED MANUAL STAINLESS WELDS 2 - 3mm: Welding stainless or alloys in this thickness range with short circuit and some of the welds may be sluggish. In contrast, the open arc pulsed MIG mode provides more weld energy, as does the start point of spray with an 035 wire with a 98 argon - 2 CO2 mix (an Ed Craig gas mix) that is if your welders know those low end spray settings.
Note: With food processing equipment stainless thin gage welds <0.100 in which an irregular weld surface has to be addressed, in contrast to short circuit, the pulsed process can provide slight cosmetic improvements, however these welds still typically are ground so what's the point?
Note The best weld quality on all stainless welds > 14 gage is derived from the TIP TIG process.
 PULSED AND MANUAL STAINLESS WELDS > 3 mm..
On stainless applications, pulsed MIG benefits are derived from the lower open arc weld energy potential than that attained with spray,, this can reduce on some parts weld distortion. However remember when you attain one weld benefit you often loose another. The lower pulsed weld energy can also lead to lack of weld fusion and porosity.
WITH PULSED MIG, WELD FUSION HAS TO BE THE FIRST CONCERN: For optimum weld fusion and the best arc stability (important attribute with high speed welds > 30 inch/min) the traditional, lowest cost MIG weld equipment and the correct choice of wire diameters - MIG gas mixes with spray transfer, would be a more logical approach than selecting the pulsed MIG mode with it's fluctuating low to peak current..
 PULSED MIG AND HEAT SENSITIVE ALLOYS: Welding duplex and any heat
sensitive alloy applications, the best manual and automated weld process is the TIP TIG process.
 PULSED MIG CLAD OR WELDS THAT BENEFIT FROM LOW WELD DILUTION: Welding clad and other applications that require low
weld dilution. Consider TIP TIG if NDT examination of internal weld quality is required or if the mechanical - metallurgical properties are a concern. Also with TiP Tip you will likely require less weld layers to attain the corrosion properties you desire.
I would consider pulsed MIG for cladding applications which have lower NDT quality and metallurgical requirements.
When manually welding most common carbon
low alloy steel applications, the purchase of costly pulsed MIG equipment, metal cored wires and three part gas mixes may provide band aid solutions but will not l not cut your weld costs or improve your weld quality. The pulsed MIG process will however add to the general MIG weld process confusion that
prevails in most global weld shops.
The weld problems most weld shops have are generated from lack of weld process expertise. Rather than reaching out for bells and whistles and magic three part gas mixes, It would be much more cost effective to provide weld shop employees and decision makers with my $400 best practices and process control training program.
There is one great weld benefit attained when you purchase those bells - whistles and sales influenced welds consumables. These purchases
provide increased profits for the manufacturer and suppliers of the products, and the added confusion they generate in the weld shops increases the shops reliance on their salesmen for weld advice..
2004: Auto parts and one of my pulsed MIG weld reports.
issue I found with your automated, Bancroft MIG welded,
stainless Torque Converter parts was the 0.053 thickness and
the wide weld gaps. On MIG welded gage parts that are less than
0.075, sensitivity to weld burn with automated applications is always a
major production concern, especially when welded with the spray mode. Also these "leak tested parts were not suited to short circuit
as this process would provide inconsistent weld fusion. The weld fusion and burn through
issue on these parts was further compounded as the lap weld variable gaps were packed with stainless mesh.
here for the rest of the story and the weld solutions.
If weld quality is your first criteria, remember, Pulsed MIG and regular TIG cannot compete with TIP TIG
When asked for his opinion on MIG spray transfer logic
MIG, a college drop out named Albert E. might have said
"It's logical that that the constant weld energy attainable
from CV MIG spray transfer, is of course a prime attribute in
attaining consistent weld fusion
and consistent weld transfer during high speed welds".
A PROCESS INVENTED BY ENGINEERS WHO DID NOT UNDERSTAND WELDS:
If you read the early
1980s research papers published on the newly developing
pulsed MIG process, one of the prime justifications for the
development of the pulsed process for carbon / stainless
steel welds was to have a weld process suited to making
weld in all positions.
1990s. Photo on right. Ed testing a pulsed MIG, STT over head weld, on
a 16 inch gas pipe pipe root. PULSED FACT: Since the pulsed MIG introduction in the nineteen eighties,
when welding many steel applications vertical up
and over head, the pulsed MIG process
has not been able to compete with the all position gas shielded flux cored wires
developed in the 1970s - 1980.
It must annoy MIG equipment manufacturers who
see great profits from the sales of their useless bells and
whistles MIG equipment, that the $1.80 lb, E71T-1 flux
cored wires can attain superior all position weld results when
used on low cost, durable, $3000, CV, MIG equipment little changed since it was developed in
the 1960s. If you want the best weld quality with all position welds, you improve the process that has always provided the best all position weld quality. That process is called TIP TIG
IT'S NOT ROCKET SCIENCE. WHEN PURCHASING MIG EQUIPMENT, WELD SHOP FOCUS HAS TO BE
ON THE WELD QUALITY ATTAINED AND THE COST OF THE WELDS PRODUCED.
If before 2006, you were a frequent user of the pulsed weld
process and you were welding carbon steel applications,
it's likely in contrast to the traditional, CV lower cost
equipment and the spray transfer weld mode, you would have
been producing steel welds on parts > 4 mm with the following detriments;  Your pulsed MIG welds were producing Inferior weld fusion,
 Your pulsed MIG welds were producing unnecessary weld porosity,
 Your pulsed MIG welds, especially with automation increased arc instability,
 Your pulsed MIG welds were made with less weld deposition rate potential.
In 2013, if you are using pulsed MIG, it's likely you are still having the above mentioned weld issues.
Of course like many managers and engineers, you may also have been using pulsed MIG
equipment for the last decade and were not aware that you
were overpaying for the MIG equipment bells and whistles and that this equipment was influencing both the weld
quality and production. Welcome to weld reality.
When examining new MIG weld technology, one should remember
that the conventional short circuit and spray transfer
modes that were developed and perfected over five decades,
also offer unique weld benefits. However the short circuit
and spray weld benefits are rarely derived from weld
personnel who have to "play around" with weld controls. To
attain MIG process benefits from low cost MIG equipment
requires MIG process expertise and that's a rarity in many weld shops.
Ed optimized both robot and manual
MIG welds for more than a 1000 companies.
A FEW OF ED'S MIG ROBOT WELD PROCESS OPTIMIZATION PROJECTS.
FORD F150 FRAMES -
VOLVO CABS - CORVETTE FRAMES - HARLEY FRAMES - NEW BEETLE SEATS
ED ALSO ESTABLISHED
THE ROBOT WELD FOR THE
WORLD'S LARGEST CATERPILLAR TRUCKS.
WELD PROCESS CHOICES ARE MADE MORE DIFFICULT, ESPECIALLY
WHEN WELDS SHOPS ARE DAILY IMMERSED IN WELD PROCESS
Many of you have worked or still work in weld shops in
which the managers, engineers and supervisors are not aware of
the real cost of that common
MIG or flux cored, 1/4 (6 mm) fillet
Many of of you have worked in a weld shop in which AWS
inspectors daily criticize MIG and flux cored weld quality,
yet these individuals lack the weld process control expertise necessary to provide the settings that would improve
Many of you have worked in weld shops in which the majority of weld personnel
daily "play around" with their MIG or flux cored weld
controls? Many of you have worked in weld shops in which the
management, supervision and engineers have an umbilical cord attached to the local weld
sales rep. This is the guy has an open door invitation to come in
and demonstrate the latest MIG gas mix, weld consumable or
Many of you will work in shops where you know the weld
decision makers who selected the costly,
sales driven pulsed MIG equipment or unnecessary three part
gas mixes, were typically not qualified to make rational
MIG weld process / equipment selection decisions.
This lack of process control expertise is common
in weld shops in which the management, supervisors and engineers have minimal
ownership of the weld equipment, processes and consumables
utilized on their weld shop floor.
DO YOU NEED TO CHANGE WELD PROCEDURES
WHEN YOU CHANGE PULSED MIG EQUIPMENT?
12/2008: Question. Ed. We pulsed MIG weld aluminum.
The weld wire most used is 4043. 3/64 and for the weld gas
we use straight argon. For a few years we have been using
Miller XMT - 304, CC/CV Inverters for our pulsed welds.
The application comprises of aluminum parts 4 to 9 mm. As
we are expanding, we are looking to purchase six new
Miller 350 pulsed MIG units, approx. price $5000.
As the lead welder, I was asked to try out the
Miller 350P. Frankly I was a little concerned about the
criteria I should use for testing new pulsed MIG
equipment. By the way I asked our CWI level 111 inspector
would we have to make any changes to our pulsed AWS
qualified MIG procedures if we purchased this equipment.
The AWS code gives no advice about pulsed equipment
changes and weld procedure data. The CWI response to the
new pulsed equipment was indifference as we were changing
Miller pulsed equipment for Miller pulsed equipment.
Answer from Ed. With the aluminum
thickness range you are welding weld fusion issues and
porosity problems are common and any weld inspector
(most weld inspectors lack weld process control expertise) should be concerned with the introduction of new pulsed
MIG equipment, irrespective of the source of that
equipment. Miller will be the first to tell you there are numerous differences between each new pulsed power source the introduce.
Lets say for example you are pulsed MIG
welding 6 mm, aluminum fillet welds with straight argon
and setting that 3/64, 4043 wire around 400 to 450
inch/min with the Miller XMT - 304. You then set the same
pulsed wire feed settings with the Miller 350P, you would
be surprised to find that you will end up with a weld
that has less weld energy providing less weld fusion. Your XMT power source, has a
different aluminum pulsed program in which the pulsed
parameters will provide higher energy welds resulting in
more weld fusion than that attained with the 350P. So using your existing weld procedures would result in welds with lack of weld fusion.
Note: With aluminum, extra weld energy also produce less
porosity. It's important to note the influence of the
weld process - application expertise (often lacking) of the individuals
who developed the pulsed programs and the sophistication
of the electronics that deliver the pulsed
welds. The bottom line is a 350 amp Pulsed MIG power source from two years ago may have little in common with that modified 350 amp pulsed MIG power source purchased today. THANKS TO PULSED MIG EQUIPMENT MANUFACTURERS
LACK OF INTEREST IN APPLYING GLOBAL WELD PROCESS STANDARD
GUIDELINES FOR THE PULSED WELD TRANSFER MODE, CHANGING PULSED MIG POWER
SOURCE MODELS SHOULD NOW BE CONSIDERED BY CODE BODIES AS AN
ESSENTIAL WELD VARIABLE, THAT IS UNTIL SOME UNIFORM GLOBAL PULSED WELD PROCESS CONFORMITY
Companies who are concerned with maintaining the MIG
weld quality they established in their weld qualification
procedures, need to be aware that when those short lived
pulsed power sources break down and are replaced, with
different pulsed MIG equipment, that at the end of the
day, unlike the lower cost traditional CV MIG equipment, the pulsed
welds produced may have little in common with the welds produced with earlier equipment utilized in producing the
original weld qualification procedure.
Of course if you
are welding thin gage aluminum parts < 4 mm, the
differences in the pulsed equipment may not be relevant,
however when dealing with code quality welds on parts
> 4 mm, the weld fusion concern factor needs to kick in, and weld
macros should be required to ensure the pulsed procedures
from the new pulse MIG are acceptable.
AN OPTIMUM PERFORMING - COST EFFECTIVE
PULSED MIG POWER SOURCE:
What do i do when testing pulsed MIG equipment? I like to be
aware of the optimum low and especially the high pulsed wire feed settings that requires high peak current. I would examine the weld deposition rate potential per application. I examine the
suitability of welds produced on the common thickness
used in the plant. If I am welding thin gage aluminum, I
look at the fast freeze characteristics of the weld and
the weld appearance. I look for the arc stability with short and long length weld cycle times.
At the end of the day. In 2013 there is still no justification for pulsed MIG equipment for welding steels. However at times when I would require a pulsed MIG unit, as this picture indicates, I have a preference for
pulsed equipment which I believe has optimum pulsed weld dynamics and good pre-programmed data. I like pulsed equipment that allows me to change
the primary pulsed parameters that are suited to my specific applications, (especially important for cladding and specific alloys). One reasonable priced, consistent performing
pulsed power source that comes to mind, is the OTC digital
pulsed MIG unit.
Note: More on the pulsed weld equipment influence in the pulsed MIG
two and in the MIG equipment evaluation section.
Weld Process Controls should always start in the front office:
From an Ed Craig report to a General Motors plant. 2001:
When your managers and engineers recognize that Weld
Best Practices and Weld Process Controls knowledge is far more important than the purchase
of costly, useless electronic weld equipment with bells and
whistles, your plants will take a giant leap towards
establishing optimum robot weld quality and productivity.
Lincoln did not "shed any light" on this
sad MIG Power Wave application:
One customer I assisted around 2005,
manufactured carbon steel street lamps 11 to 7 gage.
These are extensive yet simple manual weld applications. On the end
of the lamps a large heavy flange is welded. The flange mounts the lamp to the
floor. The flanges were 13 mm thick.
There was also a weld around the pole access box, (gage material)
located near the flange.
This simple street weld lamp application, became unnecessarily complex
the day the company decided the parts should be welded with a
The company ordered a Lincoln Fanuc ArcMate 100
robot. The robot came with the Lincoln Power Wave,
450-amp, pulsed MIG power source. The robot system was sold
by AGA who had the technical support from Lincoln and
Fanuc. Almost two years after the robot was installed the
robot had never come close to it’s daily weld
When the robot was installed, it was placed on the lamp
production line, however as numerous weld issues occurred and
the management moved the robot to another part of the plant
so the highly trained plant personnel could “play
around” with the robot weld settings.
After assistance of the so called robot weld experts from
Lincoln, Fanuc and AGA, the lamp company personnel "played
around" with the robot weld data for almost two years with
pathetic results. For the rest of the story, click here.
I hope the following comments on Pulsed MIG and the weld
process comparisons with traditional MIG short circuit,
spray and the flux cored process, will provide you or your
organization a different perspective on the rationalization
of the purchase of pulsed MIG weld equipment and the need for process expertise.
1989. Ed was invited by the Brazilian Society of
give a speech on welding in Rio. Ed titled
"Why Brazilian Engineers should avoid the robot weld
of the North American
Auto and Truck
You cannot optimize a weld process in this confused industry,
unless you can separate the mistakes of the weld industries past and be aware of the weld sales hypes that
influences too many weld shops.
< 2005: An interesting Weld
Management should ask the following
weld question more frequently.
MILLER MAXTRON AND INVISION POWER SOURCE PROBLEMS:
E-mail. From a manufacturing manager at Hayes
Lemmerz. Hayes. Ed Hayes is a global manufacturer of
car and truck wheels. We use the Pulsed MIG process for most of our
wheel welds. Since we introduced the Miller Maxtron and
Miller Invision equipment to our automated, MIG weld
production lines, we have had extensive, weld production
and rework issues. The typical wheel pulsed weld problems
that we experienced with the Miller equipment were;
 welds skipping, resulting in weld areas that contain
unacceptable and inconsistent thin welds,
 missed welds,
 welds with inconsistent weld penetration,
 weld globs,
 unexplained weld porosity,
 Inconsistent weld surface appearance,
 inconsistent weld undercut,
 numerous arc starts, weld crater and weld tie in issues,
 numerous wire burn back issues,
 extensive weld equipment break downs.
Please give us a call we would like to utilize your expertise.
At the request of the Hayes
management, I evaluated the pulsed MIG weld issues and
quickly revealed to the Hayes management the root cause of
their extensive weld issues and that root cause was the Hays management, the engineers and weld equipment. For the rest of this story click here.
Welding steels? I now consider myself an old fart who has evaluted pulsed MIG for more than 25 years and s its a rare event, I will only use or recommend "manual" pulsed MIG
when it delivers real world weld quality - productivity benefits and can therefore pay the bills.
FOR THOSE OF YOU THAT ARE LESS THAN 40 YEARS
OF AGE AND THINK I AM AN OLD FART STUCK IN A 1970 MIG
EQUIPMENT TIME WARP. MY WIFE WOULD AGREE THAT I AM OLD
HOWEVER I AM AN OLD FART THATS ASSISTED OVER 1000 COMPANIES WITH THEIR WELD ISSUES, AND BY THE WAY THAT'S NOT MY PICTURE ON THE LEFT.
in the few years I have been in this business I have set some of the world's most sophisticated automated and robot weld applications and as the corporate weld manager with ABB, North America Robot Div, I believe I have a little knowledge about robots and their weld process requirements.
As someone who has been in so many weld shops in 13 different countries, I believe I have a good grasp of weld shop culture and weld shop management.
In 2006 I was hired as the corporate weld manager with WSI, (Aquilex) . This is a company known for it's expertise in Nuclear plant weld repairs and for cladding approx 75% of the world's power plant and waste energy water wall boilers. WSI at that time used over one million pounds of stainless and inconel weld wires on automated pulsed MIG clad welds on the water wall tubes. This ASME clad application actually attained unique weld benefits from the pulsed MIG process. I was hired by the WSI engineering manager as he believed while his automated weld equipment had evolved past the complex water wall clad welding needs, the actual clad weld results from the pulsed MIG equipment and field weld personnel left more than a lot to be desired.
The pulsed clad weld quality left extensive lack of fusion, poor weld overlaps, extensive surface weld issues and unnecessary excess welds with the $26/lb, inconnel wires.
A major issue with the power plants was the clad water wall
welds too often applied too much weld heat that had a negative impact on the boiler wall longevity.
In less than three months of pulsed MIG equipment evaluation and weld process development, I developed new pulsed MIG clad weld practices and procedures that dramatically improved the inconel - stainless weld quality and lowered the weld heat. The inconel clad welds I produced, (untouched clad weld photo above) delivered over 15 lb/hr and reduced the amount of clad water wall welds required per square foot by approx. 28%. Remember this was a company that purchased over a 1 million pounds of clad weld wire for it's water wall clad applications. For this application I required unique pulsed parameters and had to develop a unique pulsed program. These were parameters that could not be attained with the Miller, Lincoln or ESAB pulsed MIG equipment that was part of the WSI pulsed MIG equip evaluation.
The important thing with any clad application is minimize the weld dilution. In contrast, the important thing with welding is attaining consistent, optimum weld fusion. What make Pulsed MIG a poor choice for many weld applications, makes it a good choice for specific clad applications. The above clad welds would not be possible with the spray transfer mode.
I started my weld journey MIG welding tractors at Massey Ferguson, Manchester UK, in the early 1960s. I wrote my first MIG weld process control article in the late 1970s. Exited at the potential of Pulsed MIG, I wrote my first pulsed MIG article for the USA. Weld Journal in the early 1980s.
During the last 3 decades I Have written four books on
MIG weld best practices - process controls and had more than 30 weld process control articles published. In this time period I was also the Weld Product and Training manager for four of the world's largest weld equipment manufacturers and suppliers.
THE BOTTOM LINE, IS I BELIEVE I AM QUALIFIED TO HAVE AN OPINION ON ANY MIG WELDS.
$10.000 for erratic pulsed MIG equipment on the left.
$3000 stable CV MIG equipment used on the right.
What the weld equipment manufacturers MIG equipment may
produce, and what most welders will never see.
As the above MIG pulsed current - weld voltage graph indicates, on the left you have a highly sophisticated Panasonic pulsed MIG power source, and on the right you have a similar parameter graph with a low cost, traditional CV MIG power source.
TRANSFERRING THE PULSED MIG WELD WIRE IN WELD DROPLETS OR A WELD STREAM, WHO CARES?
Typical concerns with pulsed MIG equipment when welding steel components.
 Pulsed Weld Fusion: A primary issue with the pulsed MIG weld fusion is this process spends 50% of it's time at a typical back ground weld current of < 100 amps.
Pulsed arc stability is important for weld quality. Pulsed MIG drops need to transfer without interuption. Pulsed welds are often influenced by the power source electronics which cannot deal with short arc lenths and wire stick out variations and the many weld - part (like mill scale) variables that can influence the weld transfer.
 Pulsed MIG and vert up welds. An issue that few weld shops think about. There is a reason why TIG welds produce the best weld quality on all position pipe welds. TIG provides constant high weld energy with very low deposition rates which require very slow weld speeds. High energy and low speeds is beneficial in attaining consistent weld fusion. In contrast, pulsed MIG provides fluctuating, moderate weld energy with pipe weld deposition rates that can be 700% higher than TIG. The pulsed MIG deposition leads to much greater weld mass and faster weld speeds than TIG, this reduces weld fusion potential.
Note: The best weld process for pipe welds is revealed at www.tiptigusa.com.
FOR DECADES THE WELD INDUSTRY SUFFERED TREMENDOUS WELD
CONSEQUENCES FROM THE ERRATIC PERFORMING PULSED MIG WELD EQUIPMENT.
2013: During the last two to three decades, most of the erratic pulsed
MIG equipment required numerous
E-Prom and circuit board changes, yet as far as
I am aware, not one of the major pulsed weld equipment manufacturers ever did a pulsed MIG power source product recall.
AN INDUSTRY THAT LACKS MIG WELD PROCESS
CONTROL EXPERTISE IS AN EASY CUSTOMER FOR WELD EQUIPMENT MANUFACTURERS THAT MAKE FAULTY MIG EQUIPMENT, OR MAKE WELD EQUIPMENT WITH BELLS AND WHISTLES THAT PROVIDES NO STEEL OR ALLOY STEELS WELD BENEFITS.
IN THE TYPICAL DIRTY WELD SHOPS, MIG WELD EQUIPMENT DURABILITY AND EASE TO REPAIR, USED TO MEAN SOMETHING:
Traditional CV MIG weld equipment used to last 10 to 20 years, and the
weld equipment repair costs carried out by the plant's
electrician was typically a few hundred dollars. Today many of the
companies who have purchased pulsed MIG equipment will pay $2000
to $5000 for pulsed MIG weld equipment repairs, and these repairs are too frequently required before the
weld equipment is 48 months old.
2013: Statistics that the major weld equipment manufacturers wont discuss.
 WHAT PERCENTAGE OF PULSED MIG EQUIPMENT LASTS
IT'S WARRANTY EXPIRED?
 WHAT IS THE AVERAGE LIFE OF A PULSED POWER SOURCE IS?
 IN A FIVE YEAR PERIOD, WHAT THE AVERAGE
REPAIR COSTS BE
FOR THE PULSED MIG EQUIPMENT?
 HOW MANY COMPANIES WHO USE PULSED MIG IN ROBOT CELLS,
HAVE HAD TO PURCHASE AN
ADDITIONAL PULSED POWER SOURCE SO THEY
HAVE A SPARE?
 HOW MANY HIGHLY QUALIFIED MAINTENANCE ELECTRICIANS FEEL
ATTEMPTING TO REPAIR A PULSED MIG POWER SOURCE?
 HOW MANY COMPANIES REALLY ATTAINED REAL WORLD BENEFITS FROM
THAT NEW COSTLY PULSED POWER SOURCE?
It's a sad reality that many companies
will pay $3000 to $5000 for pulsed MIG weld equipment
repairs, which is more than the cost of a new CV MIG power
source and wire feeder.
Remember that traditional, CV power source. It's that low cost weld power source which can provide optimum MIG - Flux Cored weld productivity and quality, that is if you provide the weld personnel with weld process control training.
This is the MIG power source
that should last one to two decades without repairs.
What helped the low durability, higher cost, more erratic, lower weld energy pulsed MIG
process become so
popular in the last two decades?  In contrast to producing traditional CV MIG equipment, when manufacturing pulsed MIG equipment, the power source manufactures can reduce their alloy, labor and shipping costs
 Like the auto industry, all MIG equipment manufactures are aware that when you add electronic bells and whistles to the weld equipment you can dramatically increase the MIG weld equipment prices.
 What motivates the weld sales rep? When you sell products with lousy gross margins your only hope is to sell weld equipment in the high dollar range and pulsed MIG equipment typically sells for 100 to 200% more than traditional MIG equipment. Also its beneficial to any sales organization that if the durability of your weld equipment is reduced, the customers will have to purchase more equipment.
Don't try this titanium weld (video below) with your
or regular TIG. the welds will fail.
Titanium Welds: TiP TiG versus the regular TIG process.
TRADITIONAL ORBITAL TIG ON
GRADE 2 TITANIUM
MANUAL TIP TIG ON GRADE 2 TITANIUM
While using the slow manual or automated regular TIG process, there is always concern about the oxidation effects on Titanium alloys.
Typically all position, manual or mechanized titanium TIG welds on parts > 3 mm will be carried at weld speeds in the 2 to 6 inch/min range. To protect those low speed, high heat welds, trailing shields are a critical weld requirement to minimize the effects of oxidation. If trailing shields are not used, the weld shop uses extra large shielding nozzles and stops the weld frequentlty to get the part under a specific temperature.
When welds are sensitive to oxidation you know weld rework and weld porosity will be an issue. The high TIP TIG weld speeds and weld TIP TIG weld agitation will produce the highest quality, cleanest titanium welds.
With either the manual or automated TIP TIG process, TIP TIG titanium weld speeds will be much faster.
The higher TIP TIG weld speeds will typically be in the 9 to 40 inch/min range. The high TiP TiG speeds enable most titanium welds on parts > 4 mm to be complete, none stop and produce produce 100% silver color without the use of a trailing shield.
TiP TiG enables better than TIG quality at MIG travel rates. This weld was made at 24 inch/min.
If your organization uses regular TIG on Titanium, you will be pleased to know that with TIP TIG, most manual or automated titanium welds will typically be done 100 to 300% faster with superior weld quality and the lowest possible weld heat.
AN IMPORTANT WELD COST REDUCTION MESSAGE TO ALL DEFENCE CONTRACTORS: As reported in the 2009. September. AWS. Weld Journal, the above (left frame) orbital Titanium welds were carried out on US Navy ships.
On one ship approx. nine orbital TIG weld units were used to weld CP Grade 2, titanium welds. The titanium welds were required on more than 12000 feet of titanium pipe which was used on each ship.
Typical automated weld travel rates from the costly orbital weld equipment was 3 - 4 inch/min. If they had selected the TIP TIG process on the orbital units, the TIP TIG welds would have been made at minimum weld speeds of 12 to 25 inch/min producing a dramatic reduction in weld heat input, (less chance for oxidization) with no weld quality issues or costly weld rework concerns. It's also reality that with the TIP TIG weld benefits, these titanium welds could be made with the same quality and productivity with manual TIP TIG welders instead of that costly automated equipment. You don't have to be an accountant to figure out the dramatic equipment and labor cost reductions (over 2 million dollars on this one weld project) if the engineers had look forwards instead of back wards.
< 2010. DURING THE LAST TWO PLUS DECADES OF SLOW PULSED EQUIPMENT
DEVELOPMENT, (THANK GOD COMPUTERS EVOLVED AT A MUCH FASTER
RATE), MOST PULSED MIG EQUIPMENT WAS PROVEN TO PROVIDE NO WELD BENEFITS FOR MANUAL MIG OR HIGH SPEED ROBOT WELDS ON
CARBON / LOW ALLOY STEEL APPLICATIONS,
YET THE MAJORITY OF NORTH AMERICAN WELD
SHOPS COULDN'T BUY THEM FAST ENOUGH.
IS THIS THE NEXT BS YOU
IN YOUR WELD SHOP?
The unique $12000 MIG power
source called called X-MIG, is controlled by a palm pilot. This power source offers artificial intelligence with adaptive synergic
controls. You know you cannot control a weld without wave forms and
X-MIG provides five million wave form variations.
With X-MIG you get fuzzy, weezy, fuzzy woozy logic and triple
AC pulsed on triple DC pulsed. X-MIG also provides a refined super adaptive turbo
pulse which gives
the arc an additional boost.
the X-MIG, is a modified short circuit mode called MSC.
Your new, X-MIG power source can also be hooked up to
the welder's cell phone or I-Pod, and controlled if you feel the
need with the palm pilot through the ethernet.
with a two week warranty, (check small print for warranty
clauses) and there is no return policy. By the way as we feel we are not responsible for the performance of this power source we feel you should be aware that it has never been field tested correctly. To order this unique,
useless MIG equipment, which cost the price of a small car,
contact the industry leaders in new weld technology, at
Could your weld shop produce a better weld than this?
Ed made the above Robot weld and the manual MIG weld below, using spatter free, MIG spray transfer from
a $3,500 traditional, CV. MIG power source that had no
CV MIG Spray weld.
The low cost, durable, 400
amp, CV MIG power source
I utilized on the above spatter free spray weld, was developed four decades before Wave Forms and Fuzzy Logic became weld weld sale's buzz words.
THE MORE COSTLY THE PULSED MIG EQUIPMENT, THE MORE COMPLEX
AND MORE EXPENSIVE THE MIG WELD EQUIPMENT REPAIRS. .WHEN THE MAINTENANCE SUPERVISOR SAW THE NEW
PULSED MIG EQUIPMENT, HE REALIZED HIS ELECTRICIANS WERE SIMPLY NOT
CAPABLE OF FIXING THE MIG EQUIPMENT.
THE SUPERVISOR HAD A DIFFICULT TIME FINDING A LOCAL
EQUIPMENT REPAIR SHOP THAT COULD PROVIDE THE NECESSARY
ELECTRONIC PULSED WELD EQUIPMENT REPAIRS WITH A QUICK TURN
AROUND. TO MAINTAIN HIS DAILY ROBOT WELD PRODUCTION. HIS COSTLY SOLUTION WAS TO ORDER ANOTHER 4 PULSED MIG UNITS AS
To purchase MIG equipment wave forms you don't need, how
much will your company this year budget for new pulsed MIG
equipment and the annual pulsed MIG weld equipment repairs?
Two weeks after the three year old warranty has elapsed on
that pulsed power source, you could end up with a pulsed
MIG weld power source repair bill that is in the $2000 to
$5000 range. The bottom line after that expensive repair,
that three year old pulsed power source is the equivalent
of a 10 year old car and you know what direction that power
source is heading.
ANOTHER INDICATION OF THE LACK OF EXPERTISE AT THE MAJOR WELD EQUIPMENT MANUFACTURES: Dec. 2008. Norfolk Virginia. I requested that the local
Miller rep bring in a Miller 350P pulsed power source to a
client of mine for a pulsed MIG demo on Aluminum. It took 10 to 15 minutes to figure the pulsed
arc characteristics were poor (insufficient energy for the
moderate rate wire feed delivered) on the 5356 program welding 1/4 (6 mm)
aluminum fillets. I switched the aluminum weld wire to 4043,
however we could not use the equipment as the 4043 program and the
arc control (voltage control) did not work. The demo failed.
TWO QUESTIONS YOU COULD
YOUR PULSED MIG EQUIPMENT MANUFACTURER.
 YOU ADMIT YOUR PULSED EQUIPMENT HAS HAD MANY
ELECTRONIC ISSUES, YET I CANNOT RECALL YOU INFORMING US
ABOUT THOSE FAULTS OR PROVIDING COMPENSATION FOR OUR WELD
ISSUES OR PROVIDING WELD EQUIPMENT RECALLS.
 AS WE RESENT BEING A TEST LAB FOR YOUR EVOLVING,
ERRATIC WELD EQUIPMENT, WOULD IT BE POSSIBLE FOR YOU TO
THOROUGHLY TEST YOUR NEXT NEW MIG EQUIPMENT WITH PERSONS WHO HAVE PROCESS / APPLICATION EXPERTISE BEFORE YOU
PRESENT IT TO THIS WELD SHOP?
Arc characteristics a minor detail for some
in the welding industry
PULSED MIG EQUIPMENT
As this MIG volt / amp graph of a 2004 PANASONIC pulsed MIG
POWER source indicates, the weld current (black) and
voltage (red) are anything but stable and the volt current spikes are unnaceptable.
Arc and weld energy stability with pulsed weld equipment is
something that should be a concern for any weld individual
that understands the importance of attaining consistent
weld energy for consistent weld transfer and consistent
High pulsed MIG wire feed rates can lead to excessive
pulsed frequency resulting in high peak current weld
content, leading to excess weld fluidity and agitated weld
Ed on right providing robot process control training for Magna plant in the USA 2004.
While at Magna,
Lincoln pulsed Equipment versus CV equipment - spray transfer.
The following weld test comparisons were made using a Lincoln pulsed power source and a low cost
MIG power source, the Lincoln CV 400. The Lincoln CV 400 costs approx. $3000.
Compare what you pay for your robot weld equipment. In 2004,
the CV 400 robot MIG package, including wire feed and
interface, would sell for approx. $6500. For those tier one
companies who often get a twenty to thirty percent discount on the weld
equipment they purchase, did you pay more than $4500 for your
robot weld package, (power source and interface). Every penny
you spent over this price was a penny thrown out of your
The Lincoln CV 400 will on the majority of weld applications outperform the much more costly Lincoln pulsed Power
Wave 455 and any of the Miller, ESAB or Japanese pulsed
equipment on carbon steel welds. In contrast to the low cost
CV equipment, the Lincoln Power Wave unit including a wire
feeder and interface will retail for around $12000 to $14000. In this segment the Lincoln CV welds are also compared with
the Lincoln Invertec, an inverter pulsed power source which
sells for approx. thirty percent more than the CV 400.
Using a low cost Lincoln 400: Ed made this untouched
"manual", 5/16, (8 mm) fillet weld. The wire, 0.045, wire feed, 450 ipm, delivering approx. 13 lb/hr.
Note: With this untouched spray
transfer fillet weld sample, no weld spatter, and the "flat"
smooth weld surface. Also note the spray weld's straight
edges which indicate consistent weld transfer and consistent
PICTURE ABOVE: With an 0.045, (1.2 mm), E70S-3 MIG wire and
argon - 10% CO2 gas mix, Ed ran the 0.045 wire at a wire feed
rate of 450 ipm. The 450 ipm is an optimum spray transfer
wire feed rate for many auto / truck frame manufactures,
robot welding carbon steel parts 3 to 6 mm. The 450 ipm
wire feed rate will enable a 4 to 5 mm fillet welds at a robot
travel rates of 40 to 50 ipm. This deposition rate will also produce a
1/4, (6 mm) fillet weld at a robot speed of 20 to 22 ipm.
Pulsed MIG versus MIG Spray.
wire set at 350 ipm.
Picture above. I produced the pulsed weld on left sample with the
0.045 wire. Compare it with the spray weld I made on the right using the
same wire size, the same technique, the same WSO and same wire feed rate using conventional CV
spray. Both welds were made with the wire feed set at 350 inch/min
delivering approx. 9 - 10 lb/hr. When set at 350 inch/min the
0.045 wire is at an "optimum" pulsed wire feed setting. The
0.045 wire set at 350 ipm is also the approx. "start point"
of spray transfer weld. Again note the pulsed weld
inconsistency is clearly evident in the convex, irregular weld surface and
inconsistent weld edges. When sectioned, you know which of
these two welds provided superior weld fusion.
If you want robot weld stability at high weld deposition
rates, purchase a CV power source and pay approx. $6000
rather than waste $12000 plus on pulsed MIG equipment. If you have
already spent your dollars on that pulsed power source and
want to improve weld fusion or arc stability switch over to
Pulsed MIG versus MIG Spray. 0.045
steel wire set at 450 ipm.
Picture Above: Again you don't have to be a weld expert to
see that when the 0.045 wire is set at 450 ipm, (approx. 13
lb/hr), which weld is optimum. The 0.045 wire set at 450 ipm
is used on many robot spray welds on parts > 5 mm. This one
picture tells you why auto industry executives and engineers
have wasted millions of dollars on paying an expensive
premium for electronic pulsed equipment that has not created
any steel weld benefits for their plants
Pulsed MIG versus MIG Spray. 0.045
steel wire set at 550 ipm.
PICTURE ABOVE: Of course if you want the maximum possible
MIG weld deposition rate or highest ROBOT weld speeds from
the robots on steel parts > 8 mm you will use an 0.045
wire set around 550 ipm, 15 to 16 lb /hr. This is a common
spray wire feed setting you don't want to set with that
costly pulsed power source. One thing you can say for the
pulsed process, at low or high wire feed rates the weld
inconsistency is consistent.
IT'S ALSO TRUE WITH 0.035 (1mm) WIRES.
PICTURE ABOVE: With the 0.035 wire and argon 10% - CO2. I
opened the wire feed control to it's maximum setting and
provided a wire feed rate of 700 ipm. Again look at the spray
weld on the left versus the pulsed weld on the right. The
pulsed weld with the 0.035 wire indicated the same
inconsistent weld transfer pattern as with the 0.045 wire.
The pulsed weld was again more irregular and convex and the side wall weld
fusion was again less inconsistent than the spray weld. Again
note both welds are untouched with no spatter.
In the pictures below the 0.035 wire was set at an optimum mid range pulsed wire feed rate of 550 ipm Compare with the MIG spray weld made with the same wire feed rate on the
right and you can see which weld is more stable.
Picture Above. Again note the 0.035 wire comparison of the
pulsed mode versus spray transfer weld. In the pulsed picture
on the right, the welds are made at a mid range wire feed
setting of 550 ipm. As the weld indicates again the
traditional spray mode shows more consistency in the metal
If you want the most effective robot and manual MIG
flux cored weld process control training program,
Ed's process control training resources.
Pulsed MIG welding Torque Converters:
This costly LINCOLN POWER WAVE,
was not up to the following simple wheel weld challenge,
After years of trying to educate an apathetic big
three weld management, it's only fitting that my last auto weld
consulting job in the year 2000, ended up in a Detroit
General Motors plant and the application was using the
infamous Lincoln pulsed MIG equipment.
The GM management and engineers who typically like Ford and Chrysler engineers are not aware of the process fundamentals that weld their vehicals were
not satisfied with their new multi-million dollar torque
converter line pulsed MIG welds. This line had been set up to
automatically pulsed MIG weld approx. 1000 torque converters
The GM torque converter parts are delivered to the weld
stations by conveyors. In the weld cells, the round parts
rotate while the MIG welding guns are stationary. The parts
required a continuous 3/16 (4.8 mm) horizontal
Each weld station had three MIG guns which would
simultaneously weld the converters as they rotated. The
pulsed MIG weld problems generated from the Lincoln equipment
and a process that often does not deliver optimum weld quality delivered a product with the following;
[a] The torque converters had a 4 - 8% leak rate from the multi MIG pulsed welds. In
the auto industry this leak rate in some plants would be
considered good, however at this GM plant, as the weld production
volume was extensive, the finished machined torque converters
were very costly and weld repairs were not allowed.
[b] Excess weld heat from the multi-torch operation was
also causing production "assembly" issues.
The Lincoln pused weld equipment arc weld instability at recommended pulsed wire feed settings established by Lincoln
engineers and technicians caused extensive weld quality issues, weld rework and
productivity issues for GM. The GM engineers had worked out the
annual weld rework and loss of productivity losses for this
plant would be in the range of 1.5 to 2 million dollars. For
a little weld process logic from Ed who fixed the problem and never even got a thank you card from Lincoln and for the the rest of the story
2004. Another Pulsed
MIG Problem from Miller and I was
wondering, do those guys at Miller know what defines a good weld?
and do they ever
test their pulsed MIG equipment before they release the new models?
2004: This time my pulsed MIG application was a major tier one
manufacturer of stainless exhaust coupling and flexible
fittings as used in the auto / truck industry. The tight
tolerance, stainless parts, are rotated in an automated
Bancroft welding machine with the single MIG gun stationary. The stainless MIG welds were made
inside the flange. With these automated parts I was again provided
the opportunity to evaluate pulsed MIG versus traditional
To weld the stainless coupling parts, the manufacturer had
selected Miller Invision pulsed MIG
equipment and the weld transfer mode utilized was the pulsed
MIG mode. The 0.045 (1.2mm) 300 series stainless weld wire
was set at what should have been an an optimum,
conservative pulsed wire feed rate of 300 ipm with optimum weld volts. After
welding each part, the parts were leak tested. The pulsed
welds looked good, yet the average weld rework as revealed
by the leak test was over ten percent.
To fix the leaks, I first switched off the pulsed mode and
within a few minutes established new "spray transfer" weld
parameters. With the spray mode I set the 0.045 wire feed
rate higher, at "400 ipm". With the higher spray wire feed
rate I increased the actual weld production by 25%and the leak test for the new spray transfer welds was "zero
AS THE WELD TRAVEL RATE AND WIRE STICK OUT WAS CONSTANT, THIS WAS A GREAT APPLICATION TO COMPARE THE MILLER PULSED
MODE WITH SPRAY TRANSFER. To reevaluate the pulsed mode at
the same wire feed rate set with the the spray weld, I then
reset the Miller Invision power source back to the pulsed
mode and set the pulsed wire feed rate at 400 ipm. I then
fine tuned the pulsed parameters to minimize spatter with
the shortest optimum arc length. The new pulsed welds looked as
good as the spray welds, however when the parts were leak tested approx. 8% of the pulsed MIG welds required
weld rework. I turned the pulsed mode off and from 2005 and
these important auto / truck part welds are made the old
fashioned Ed Craig way, using "spray transfer".
WITH PULSED MIG, IT'S OFTEN WHAT YOU DON'T SEE WITH THE
WELD THAT SHOULD BE A CONCERN.
For those of you struggling with consistent pulsed MIG
quality welds, be aware that
in most instances the traditional spray transfer arc on
parts > 3 mm can provide superior weld fusion and be
As much as weld equipment companies benefit from
making their weld equipment complex and costly, please note MIG welding has never been rocket science. The wires in your $10 Chinese
toaster provide the correct amount of resistance and
current to maintain the wire in a consistent red heat
As the photo on the right indicates, for a few hundred
dollars, you can put two car batteries together. With the
24 volts hooked up a small spool wire feeder gun you can
then produce an excellent MIG weld.
In the simple task of melting the tip of a small diameter,
MIG wire, weld equipment manufactures today don't blink as
they offer a sophisticated, electronic pulsed MIG power
source at the cost of a small car. If you have more money than sense you know you need pulsed MIG equipment for you steel welds.
Miller Pulsed MIG Update 2008. It's the same
stainless coupling company I visited in 2004, only this
time we compare the Miller Axcess pulsed mode against lower
cost CV equipment and the traditional spray transfer
In 2004 when this auto parts supplier had problem with the
Miller Invision pulsed MIG flange welds on the stainless
couplings, I found that we could get the consistent weld
results the company desired by switching the pulsed mode
off and welding the the flange stainless welds with spray
transfer. (See above story).
In 2008 Miller delivered it's new Miller Axcess with a promise
that the pulsed mode was now stable and would achieve
the desired weld quality on the automated
stainless coupling welds. The coupling company was dubious about Miller's promises so they invited me back to compare the
Miller Axcess pulsed mode against the traditional spray
mode I had previously established.
The automated pulsed MIG weld cells had a two torch setup. I set one gun
on the Miller Invision in the traditional spray mode.
I set the other gun to a new Miller Axcess
and utilized the Accu Pulse mode. I ran both systems using the
shielding gas I developed for this weld, Argon - 5 CO2. We used an 0.045
(1.2mm) stainless weld wire. The wire feed range tested was
300 to 500 ipm.
In the weld tests the Miller Axcess
performed well in the pulsed mode. With both the pulsed arc
and spray arc lengths finely tuned to minimize spatter. The weld results were again
interesting. The Axcess package is priced about 50% more
than a standard CV Miller Delta Weld package, however the Miller Axcess pulsed mode did no
better than the regular MIG spray mode. It's true that the average weld
current from the pulsed mode was less, however lower
current on this application which was subject to leak tests was not a
benefit. As for weld spatter, the coupling weld position
and small ID create an excellent weld spatter trap, so weld
spatter was a major concern. Again the Axcess did well on
the spatter count, however the spatter results between the
pulsed mode and spray mode were so miniscule that when the
pulsed and spray parts were placed side to side, no one
could tell which was the spray weld and which was the
pulsed weld. The important bottom line for this company was there was no justification to pay the extra price for the Miller Axcess. In the afternoon I fine tuned the traditional spray mode and the
afternoon shift ran 800 parts that required no weld cleaning and no weld rework.
IT'S LOGICAL FOR ANY WELD SHOP TO ASK, WHAT REAL WORLD WELD BENEFITS ARE
DERIVED FROM MAKING THE MIG WELD EQUIPMENT
MORE COSTLY AND COMPLEX?
WHAT DOES THE PULSED MIG EQUIPMENT HAVE TO DO TO
MAKE THAT COMMON 1/4 (6 mm) FILLET WELD? As the pulsed MIG weld wire travels into the weld at
typical speeds of 100 to 700 ipm, that highly sensitive,
artificial intelligent pulsed MIG power source has to;
[a] Control and diagnose both the pulsed arc start and arc
end weld parameters. If the preset pulsed data does not
produce the weld start or the weld end crater will your
weld personnel know how to set the correct pulsed data?
[b] Control and diagnose the pulsed low back ground
current. If the weld is unstable or lacks weld energy, does
your weld decision maker know what the optimum pulsed back
ground current should be, or what an adjustment to the back
ground current will do to the arc or weld?
[c] Control and diagnose the pulsed high peak weld current.
Does your weld decision maker know what the optimum pulsed
peak would be, or what an adjustment to the peak current
will do to the arc or welds?
[d] Control and diagnose the pulsed frequency. Does your
weld decision maker know what the optimum pulsed frequency
should be, or what an adjustment to the pulsed frequency
will do to the welds?
[e] Control and diagnose the pulsed pulsed up-slope / down
slope and the pulsed profile. Does your weld decision maker
know what an adjustment to the pulsed profile, (select one
of 4 million available wave forms) will do to the
FOR DECADES SPRAY TRANSFER HAS BEEN A SIMPLE PROCESS, YET
FEW WELD SHOPS PROVIDED THE PROCESS TRAINING NECESSARY
TO ATTAIN PROCESS OPTIMIZATION.. IN CONTRAST TO THE COMPLEXITIES ASSOCIATED WITH PULSED MIG,
LOOK HOW SIMPLE IT IS TO MAKE THAT COMMON STEEL FILLET WELD
FOR ANY STEEL OR STAINLESS APPLICATION, USING A CV POWER
SOURCE, AN ARGON CO2 MIX AND 0.045 (1.2 mm) WIRE:
 You set the optimum spray weld voltage, one of two
settings (from my weld
books and training resources)
then fine tune the voltage by the sound or spatter length
If the weld shop was confused about
the two control short circuit and spray modes.
what hope does the shop have understanding pulsed
MIG if pulsed parameter adjustments are required?
A traditional CV, MIG power source may be
short on electronics, however it does a great job while
welding as it automatically maintains the arc length during
wire stick out variations.
The low cost, durable MIG equipment provides three unique
MIG weld transfer modes suited to all metals. Short circuit
provides controlled low heat input suited from 20 gage to
0.100. Controlled globular produces a small amount of weld
spatter and suited to weld 14 gage to 0.125 and depending
of the use of robot or manual welding, spray is suited to
welding all steel parts >0.070.
WHAT ABOUT THOSE INVERTERS OR CC/CV MULTI-PROCESS
POWER SOURCES?.....Did you know the regular lowest cost CV
power source is superior to an Inverter and a multi-process
or pulsed power source when used for the MIG weld modes,
short circuit or spray and for welding with the gas
shielded flux cored wires?. (This info is not available from Miller, ESAB or Lincoln, however the evidence is available in my MIG training resources.
There is a great value for any weld decision maker, when
they combine weld process expertise with a $2000 - $3000 CV power
source and a simple two part gas mix that can handle the vast majority of the world's
Ed providing MIG and flux cored process control training
and managers from 6 countries.
2010: MIG WELD BEST PRACTICES AND PROCESS CONTROL
TRAINING FOR WELD OPTIMIZATION. MOST COMMUNITY COLLEGES
DON'T PROVIDE IT, UNIVERSITIES THAT OFFER WELD ENGINEER DEGREES
DON'T DO IT, COMMUNITY COLLEGES THAT TEACH WELDING RARELY DO IT, AND WELD SHOPS GIVE IT MINIMAL CONSIDERATION .
IF THE WELD PROCESS CONTROL TRAINING IS PROVIDED FROM MY CD,
MIG AND FCAW POWER POINT PROGRAMS, THE WELD RESULTS FOR YOUR
ORGANIZATION CAN BE REMARKABLE.
[a] WELD PERSONNEL WILL NO LONGER HAVE TO "PLAY AROUND WITH WELD
CONTROLS" TO ATTAIN OPTIMUM WELD DATA.
[b] WELD PERSONNEL WILL KNOW WHEN TO SWITCH FROM SHORT CIRC,
GLOBULAR SPRAY OR PULSED OR WHEN TO CHANGE THAT WELD WIRE
SIZE OR GAS MIX FOR OPTIMUM WELD QUALITY AND
[c] WELD PERSONNEL WILL IMMEDIATELY UNDERSTAND THE ROOT CAUSE
OF THEIR WELD ISSUES AND WILL PROVIDE INSTANT WELD PROCESS
RESOLUTIONS NECESSARY FOR THE COMMON ALL WELD ISSUES.
[d] WELD PERSONNEL WILL UNDERSTAND THE RELATIONSHIP BETWEEN
WELD COSTS, WIRE FEED SETTINGS AND THE WELD DEPOSITION RATES
THEY DAILY ATTAIN.
A FEW OF ED'S WELD PROCESS OPTIMIZATION PROJECTS,
FORD F 150 FRAMES -
VOLVO CABS - CORVETTE FRAMES- HARLEY FRAMES -
NEW BEETLE SEATS
ED ALSO ESTABLISHED
THE ROBOT WELDS FOR THE
WORLD'S LARGEST CATERPILLAR TRUCK.
Why not give the personell who make weld decisions this
FUNDAMENTAL MIG WELD PROCESS CONTROL TEST
HOW FAR IN THE WELDING INDUSTRY DID WE EVOLVE BETWEEN 1988
AND 2008? In the graphs below we have two MIG welds both
set with optimum weld data. If you believe in the
importance of MIG arc stability take your choice. Compare
the spray voltage (red) and current (black) graph on right from a
regular $2000 MIG power source built in 1988, with the
optimum pulsed mode graph on the left from a $12.000 USA
manufactured pulsed power source built in 2008.
Even lawyers could figure
this weld equipment performance graph out.
In one weld process control presentation I provided a process control work shop with a large group of
ASTEC / Kolberg managers and engineers. There was two lawyers present,
ready to give a talk on patents. I asked the lawyers which
of these graphs they would accept in the attainment of consistent,
optimum MIG weld quality. You know they both picked the one
on the right.
The next two pictures are are two 3/16 (4.8 mm) fillet
welds I made during 2003 on 1/4 stainless steel. The welds
were made with a Lincoln 300 Power MIG. The 300 power
source was a single phase, pulsed MIG unit that retailed at
that time for approx. $3,700. This pulsed MIG power source
has pre-scheduled pulsed programs for specific wire types
This Lincoln pulsed MIG power source was purchased by a
company that welds both steel and stainless parts. Due to
it's daily welding issues, (most caused by lack of process
expertise) this company believed it needed Lincoln's so called unique pulsed
power source. The MIG wires used for the 3/16 fillet welds were
0.035, (1mm) - 308L and 309 wires.
With the Lincoln power source, I set the 0.035 wire feed at
550 ipm, a setting that should have been an optimum pulsed
wire feed rate. The power source provided the pulsed
parameters, I simply had to set the trim, (fine tune the
weld voltage) to attain the optimum pulsed arc length. The
manual welds were untouched after welding. Take note of the
mediocre pulsed weld appearance and also the heat affected
zone in contrast to the spray photo.
Th following pulsed MIG picture is worth a thousand words. Provide a macro
examination of your pulsed MIG weld fusion and then compare with spray transfer.
$3700: Lincoln 300. Pulsed MIG "On".
Lincoln 300: Same wire feed settings as above
with the pulsed mode turned "off".
With the pulsed mode switched off, the Lincoln 300 power
source was set to spray transfer. The same weld wire and
wire feed rate as the pulsed weld were used for the 3/16
stainless spray transfer fillet weld. As you can see above,
even the spray weld was poor with an obvious lack of weld
energy. Poor slope output for spray is common from pulsed
MIG equipment. As you can see when comparing both welds
even the HAZ is similar. My point is simple. Why pay extra
for the pulsed electronics when you don't need them? Why
pay for something that provides inferior performance to
traditional CV equipment and is less durable and more costly
Check the weld similarity
from the two weld transfer modes.
Check out the Lincoln poor performance for both the pulsed and
The above welds would be dramatically improved using the
same wire feed settings and spray transfer from a regular
> 250 amp CV power source. So we have another weld shop
that purchased a pulsed product that did not live up to the
IF YOU WANT TO FIND THE WORLDS WORST WELDS
PAY A VISIT TO AN AUTO / TRUCK PLANT
The following pictures are robot pulsed MIG welds made
between 2003 and 2005 on Ford truck frames. The sad looking
welds were made with one of the most expensive, American
manufactured, pulsed power source available, the "Lincoln
I have been in too many auto / truck frame plants and from
a weld perspective it was always a gut wrenching,
frustrating experience. I often think the coating they put
on the frames after welding is not there to prevent rust,
it's there to either hold the steel together or to make sure no one can see the welds. The
pathetic Ford truck welds shown below are of course not the
fault of the workers on the floor and not the fault of the
robots or weld equipment.
2003 - 2004. Weld Equipment.
Lincoln Pulsed Power Wave purchased by managers
who lacked the ability to take ownership of a aimple welding process.
These Ford truck robot MIG welds were
managed and programmed by engineers with degrees and robot weld personnel who thanks to their inexperienced management were not given the training required to
Best MIG Weld Practices and Robot Weld Process Controls.
Purchase the most expensive and
most sophisticated electronic MIG equipment available. Make some bad choices on the weld
wire size selected. Mix in inexperienced, hands off weld
management. Toss in some poorly trained engineers,
supervisors and technicians and you to will have the right
combination to produce truck frame welds that look like
they fell out of the rear end of a pigeon as it flew over
What a combination, America's most expensive pulsed power
source welding on America's most expensive truck, it was a lousy marriage. Here in
the USA we can blame the loss of many jobs on overseas
lower labor costs or superior Japanese quality, which from
a weld perspective is simply a myth. If we face weld
reality, we may want blame a good portion of the demise of
the Big Three and North American job losses on under
qualified, manufacturing management who for decades lacked
the ability to control and optimize the equipment they
own and therfore lacked the abilty to recognize the process control training necessary for their plant employees.
Remember optimum MIG welds
with the best possible weld fusion are not about a unique weld transfer mode such as pulsed, and so called unique wave forms, they are about a balance between the stable weld energy
(slope output) delivered and the weld deposition rates and travel speeds provided.
Visit Ed's Weld Process Control Training Resources.
THE FOLLOWING IS A CASE OF WELD PRODUCT MARKETING /
SALESMANSHIP AND BOVINE FECAL MATTER THAT FROM MY
PERSPECTIVE IN HAS REACHED AN ALL TIME LOW.
I was amazed to read one advertisement in the Nov. 2003.
Weld Journal, a magazine that often struggles to walk a
line between it's source of advertising revenue and
maintaining unbiased weld technology credibility. The advertisement in the Weld Journal was from National
Standard, (NS), a primary North American MIG wire
manufacturer. The NS advert made ridiculous
claims for it's new Pulse PLUS Steel MIG Weld Wire.
National Standard claimed. "That with their unique MIG wire
and the pulsed MIG process you will get less weld
spatter, less weld fumes and their MIG wire will
reduce the need for grinding. NS also claimed that
their pulsed wire is supposed to provide a wider
operating range than competitive MIG wires. NS made four claims
that were simply four lies.
BS from NS with it's so called Pulsed MIG Plus MIG
When an industry MIG wire leader like National Standard has to rely on marketing BS
you know there will always be a salesman ready to deliver the BS. A sad point also
is the the USA Weld Journal printed the above add.
I guess that $12000 pulsed power source you just purchased
from Lincoln that's loaded down with sophisticated
electronics that controls the pulsed weld transfer, will
now with the magic NS wire provide an enhanced pulsed transfer.
This type of weld product advertising belongs on the very
top of the the mountain of the never ending Bovine Fecal
matter that for decades has spewed from the marketing
department many global weld equipment and consumable
manufacturers. This is the type of weld BS data that adds
to weld shop myths and weld shop confusion. This is part of
the the BS that has helped destroy the technical
credibility of today's welding industry.
SHAME on National Standard, a major North
American weld wire manufacturer for it's gross product lies
and complete lack of respect for the intelligence of it's
North American welding customers.
SHAME on a Welding Journal affiliated with the
none profit American Weld Society for providing this ad.
This is a journal that prides itself on it's technical articles, perhaps this journal forgot that it only benefits it's "paid subscribers" as long
as the information and advertising it provides is
SHAME ON the welding industry that's been
using the MIG process for more than five decades, an
industry which still has many gullible readers that
actually believed the NS claims and purchased this
ridiculous MIG wire.
This NS MIG weld wire fiasco, is yet another reason why it's
important that the global weld industry needs to take
ownership of it's processes and why weld decision makers
need to cut the umbilical cord that has been attached to
weld equipment and consumable manufacturers for more than
< 2005. When it comes to reading advertisements
and welding literature written by personnel who work
for world's leading MIG equipment and consumable
manufacturers, before you believe what you read, put
that weld shield in place, check the wire feed
rates you can deliver, examine the arc and weld consistency,
THEN CUT THE WELDS AND
BELIEVE IN THE WELD FUSION YOU
SEE. Ed Craig 2005.
E- Mail Weld Question
June 19, 2003.
Subject: GMAW-P Problems.
Hello Ed. We are trying to
utilize GMAW-P on an HY-80 steel pipe welds. I was pushing
for gas shielded flux cored wires, but our engineers will
not allow flux cored wires for our procedures. The
engineers complain of poor mechanical properties from the
flux cored wires on the HY metal. We can't use spray as
many of the welds are out of position. We are having a
difficult time passing UT with our Miller Invision pulsed
power source. The MIG pulsed parameters required provide a
wide arc zone and long arc length, this results in
inconsistent weld fusion.
We are thinking about switching to Lincoln Pulsed
equipment, as they tell us with their equipment that we can
control the pulsed wave forms and get better results. The
Miller Equipment does not allow wave form manipulation from
the interface, you have to run off the factory resets. Do
you have any suggestions on getting better results with our
Ed's Reply: Forget that nonsense about "pulling a magic
wave form out of that red machine". Your question brings to
light some of the pulsed process issues I have been talking
about for more than a decade. Pulsed variable parameters
and pulsed arc length sensitivity combined with a lower
energy, fluctuating pulsed MIG arc plasma will have welding
consequences especially to those who are concerned about
the weld fusion attained. Of course to attain more weld
energy with pulse one can always increase the pulse
parameters. However there are limits and when those
parameters are outside the optimum pulsed parameter range,
you will not likely be pleased with the resulting
Good luck with the Lincoln Power Wave and it's numerous
I think you will find that wave form control which sounds
great in the Lincoln marketing brochure is going to have
have little impact on your weld applications. You may want
to read one of my many experiences with the Lincoln Power
Wave when it created serious weld quality issues for
American Axle, a major tier one axle manufacturer. Check
out the MIG equipment section.
Your statement on the engineers
comments on unacceptable gas shielded flux cored weld
mechanical properties shows a real problem in your
organization and a common major problem for many
If your company is interested in attaining consistent weld
fusion and higher than traditional weld strength it should
fire the engineers who made the ridiculous flux cored
statement and quickly get used to welding with the highly
cost effective gas shielded flux cored consumables or better still take a look at TIP TIG.
Your companies weld issues are typical of many companies in
the pipe and pressure vessel industries, companies where
you will find many engineers who provide MIG and flux cored
weld opinions, yet few are qualified to make a rational MIG
or flux cored weld process decision.
E Mail 01/ 2005.
Question: Ed I just recently purchased the Lincoln Power
wave 355 Pulse power sources to weld 0.055 stainless steel
pipe to a much thicker 6 mm solid donut shaped carbon steel
part. These are automated welds and the nozzle to work
distance is fixed. I have been experiencing arc stability
issues and INCONSISTENT weld appearance every now and then
during the circumferential welds. Could I talk with you in
more detail regarding this problem?
Sincerely. Travis Schifferns.
Ed's answer. You are
finding the weld reality that the pulsed equipment you
purchased does not live up to the promises made by the
equipment mfg. Call me reference the solution to this
ROBOTS AND HIGH SPEED PULSED MIG WELD CONCERNS: The pulsed,
inconsistent, lower open arc energy attained from < 2005
pulsed equipment was not the logical choice for many high
weld speed robot applications, especially when you consider
the two prime weld quality issues on many robot welds on
steel or stainless parts > 4mm was;
 marginal or lack of side wall weld fusion.
 inconsistent or skipped welds caused by inconsistent
transfer of the electrons across the arc.
SPRAY VERSUS PULSED PLASMA
AND THE WELD STREAM:
In contrast to the ever changing, peak to back ground
pulsed MIG transfer mode, the constant energy, higher
velocity, denser plasma with the spray transfer weld
stream, offers three unique weld attributes;
 Spray Transfer: With consistent weld parameters, spray
transfer will provide a less fluctuating, more consistent
plasma shape and therefore maintain the
location of the arc plasma energy influencing the weld
fusion potential. In contrast to spray, the pulsed plasma
is typically weaker as 50% of it's time its at the back
ground current setting. In the pulsed back ground to peak
condition, the plasma profile continuously collapses
between a narrow and wider plasma.
 Spray transfer can weld with a much shorter arc length
than pulsed. The shorter arc length focuses the most
concentrated area of the arc plasma plasma energy in the
weld rather than over the external weld surface. The
concentrated, higher energy spray plasma is beneficial to
attaining optimum weld fusion and stable electron transfer
with high speed welds.
 The traditional spray transfer plasma configuration and
short arc length potential can provide an arc less
sensitive to mill scale or specific coatings.
THE WONDER OF THE REGULAR MIG ARC: When you read anout the pulsed MIG
electronics performing miracles as the MIG arc lengths
change, remember In most robot and automated welding
systems, the MIG arc length (wire tip to work distance)
variations that take place during the welds should be
minuscule. However if the constant voltage (CV) arc length
does change during the weld, the traditional CV MIG power
source has always had that unique slope feature in which a
small voltage change in the arc will result in a high rapid
weld current change that instantly "self corrects the arc
E-mail from l. KD - P&F. 12 /07
Ed, you would be interested to know that by the end of
the year I will have at least 100 of our robots welding
with US 0.035 (1 mm) wire using conventional spray
transfer with "no pulsing". It took 10 years Ed, but we
are finally using the recommendations you made to us in
the nineteen nineties. I now have the top guy in North
America convinced traditional spray is the way to go with
the robot MIG applications. In regards to your MIG
process control training programs and resources we now
have two other plants that will be contacting you.
Note from Ed: This is one of the largest
tier one suppliers to Honda and Toyota in the USA. The
plant has hundreds of Panasonic robots and Panasonic
pulsed MIG equipment.
The Panasonic weld equipment and pulsed process was a
requirement of the Japanese parent company. For more than
a decade, this pulsed MIG equipment which should never have ben sent to the USA, daily generated
numerous weld and production issues that
dramatically impacted the daily robot weld quality and
production. With all the problems, the blinkered
corporate engineers and apathetic, inexperienced managers in Japan were
reluctant to hear that the the traditional, more durable,
lower cost, North American CV MIG equipment and logical Swedish robots would provide
solutions to the majority of their daily robot weld
Many Japanese companies are hobbled daily
with their Achilles approach to manufacturing. What is
that Achilles heel? It's an arrogance that what they do
is superior to anyone else. Bringing erratic performing
Japanese weld equipment and Japanese MIG wires to America
was like sending second grade coal to Newcastle, UK. The
costly Asian weld wires provided no benefits, the
Panasonic weld equipment was a disaster of inconsistency
and erratic performance of the Panasonic Japanese robots left
a lot to be desired.
Thanks to the Japanese general lack of MIG weld process expertise,
their lack of flexibility to make changes when change was
required and there disregard of the process advice I
provided them 10 years previously, I believe this company
has wasted at least 20 million dollars in robot down
time, rejects and rework. But I suppose the important
thing is the Japanese engineering egos are still intact.
Dont forget the influence of the spray weld gas
ON THE STABiITY OF SPRAY TRANSFER WELDS.
GAS MIXES CONTRIBUTE TO THE WELD
STABILITY, WELD ENERGY & WELD OXIDATION.
In a time of equipment electronic bells and whistles,
please remember with MIG gas mixes, that the CO2 gas
dissociation and oxidation properties, are often not given
the credit or consideration they deserve.
Ed introduced 4 important gas mixes in North America and recommends you
visit the MIG gas section of this site.
The Japanese will often add electronics to MIG welding
without understanding why they added the electronics
E-mail. Oct 2008:
I am emailing you because I have come to a questionable
snag with my pulsed MIG equipment. I have the equipment set
in the spray mode. I am welding on 5/16” carbon steel material, my
settings are set to spray transfer (29 volts 500 wire speed
When making a 3/16” fillet weld with the 0.035 wire I
have noticed that at the end of the weld, the weld flattens
out and has what I have been taught to refer to as a
“fish eye” ( I am not sure if this is the right
term for this problem ).
The attached photo will show you what I am referring to.
When coming to the end of my weld I back over the weld
about ¼” instead of just stopping. I don’t
pull my nozzle away before I let the trigger go, so I
don’t think this issue is caused due to the length of
the stick out. My gas is set to 35cfh argon/CO2 mix.
Could you please advise what may be causing this poor
finish is this just cosmetic or an issue that needs to be
addressed? If this is an issue that needs to be addressed
could you please explain the proper procedure for fixing.
These parts are under extreme vibrations and some stresses
Vertical / Horizontal and Lateral. Thank you.T
Ed's Reply. Two things going on here.
 First the weld picture indicates poor side wall fusion.
As you are using good spray parameters the lack of fusion
is likely a result that the weld surface was wire brushed, however
the mill scale has been left. If you are concerned
about fatique properties you don't MIG weld over mill
scale. Grind the weld area before welding, I am sure you
will see a difference in the weld appearence.
 A fish eye is typically a pore evident in a failed weld
and the bright shiny appearence in the pore indicates the
presence of hydrogen, so you dont have a fish eye. You do
have a pulsed power source that has a built in defect. This
is a a commom classic issue with pulsed equipment in which
the machine controlled end parameters or burn back
parameters are set too high, (more evidence that pulsed
equipment manufactures don't correctly test the equipment
they build.) I see this defect all the time in pulsed equipment in robot
cells. At the end of the weld, the high voltage spike
applied for the burn back causes a suck back effect in the
arc leaving that classic hole in the crater. In many
instances if you examine with magnification you will find
shrinkage cracks around that hole and with your fatigue
concerns, this defect has to be ground out and the crater
filled in. My MIG process control training resources deal with this
issue and provide process solutions, however you would be
well served to send the power source back to the company
who manufactured it. It's ironic that this defect would not
occur on a lower cost traditional CV power source.
THE PULSED MIG PROCESS HAS MORE THAN ONE ACHILLES
HEEL: Even with the world's best pulsed equipment, on many
common applications the Pulsed MIG process will always have
its Achilles Heel. Visit section 2 of pulsed MIG. Find out
about useless wave form options and concerns for lack of
Invest in your weld career, its your choice talk to a salesman or order
Ed's books and MIG
and flux cored, manual or robot weld process control CD training
IF WELD QUALITY IS YOUR FIRST CRITERIA,
PULSED MIG WILL NEVER COMPETE WITH TIP TIG
Pulsed MIG Section 2.
 Take a look at the Panasonic Ripple Farce.
 This tractor mfg paid extra when they took their advice from a weld salesman.
 The Miller pulsed MIG equipment fiasco.
 Lincoln Power Wave caused Ford Truck axle cracks,