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The following is an email sent to me March 2001, I deleted only the name of the individual and company name. If any of you have serious robot issues why not email me.

Ed, we are on our 4th generation of Motoman robots here at _______, and I didn't think they could get any worse, but I was wrong. Ed, I simply would not recommend the new UP/XRC robots to anyone. We have had nothing but problems with them. Motoman has a real problem with the encoders in their motors, and we have replaced everyone at least once. In addition, I have a servo pack or motor go out on an average of once per week. They are also having wire harness problems with the insulation prematurely wearing out. I have had to replace four so far, and we have only been running since August. We have also had to replace 13 boards in the main processor. They are saying that the Panasonic power sources are creating noise in the unit and taking out the boards, but we are not really buying it and neither is Panasonic. What a nightmare.

Now, let's compare this to our Canadian facility which uses mostly Fanuc on the same lines designed to produce the same product. I spoke with their technical manager last week and he has not had any warranty claims since start-up. If you total up what would have been my repair expense, if the robots were not under warranty, I would have spent in excess of $175,000.00


[1] If you have robot weld rework on more than 2% of your parts.
[2] If you utilize three part gas mixes for carbon steels or thin gage stainless.
[3] If you believe you can produce welds with a Metal Cored wire which you cannot do with a lower cost MIG wire.
[4] If you utilize flux cored wires for welding clean carbon steels <3/8 in the flat and horizontal welding positions.
[5] If you weld carbon steels and you use mixes containing oxygen.
[6] If you purchase your primary weld supplies from more than one supplier.
[7] If the person who has full responsibility for the robots is in the union.
[8] If your company allows operators or anyone other than the programmer to make welding parameter changes to the robot program.
[9] If your purchasing personnel make decisions on the consumables selected.
[10] If there is no weld parameter data posted on the weld equipment or along side the robot cells.
[11] If your manual welders daily use a whipping action or weave action with their MIG guns.
[12] If your robots have a ROBOT down time per shift of more than 15 minutes.
[13] If you use pulsed MIG and don't know how to provide optimum pulsed parameter adjustments, or you are not aware how your pulsed weld deposition rates compare against the lower cost spray transfer.

The three welding products that have had the biggest growth in welding shops during the last decade are,

[1]Three component gas mixes
[2]Metal cored wires
[3]Pulsed MIG equipment


MIG weld gas reality
Back in the sixties the British Welding Institute carried out GMAW gas research that indicated in contrast to argon 10 to 20% CO2 mixes, three component gas mixes containing argon - CO2 -oxygen when used for welding carbon steels "provide no practical weld benefits". Adding oxygen to an argon CO2 mix simply lowers the weld energy lowering the weld fusion potential increasing weld porosity potential. The biggest selling gas mix for stainless is a tri mix that contains helium - argon - CO2. This TRI-mix when used for welding most thin gage short circuit applications cause more welding issues than a lower cost two component gas mix. See the MIG gas section and invest in my books for practical weld gas data without marketing or sales bias.

Pulsed MIG reality
After two decades of use in North America many experienced weld decision makers are still trying to figure out the benefits of the pulsed MIG process for MIG welding "carbon steel" applications. In contrast to a traditional, durable, low cost MIG CV power source that provides optimum short circuit and spray transfer, pulsed MIG equipment when used for carbon steel welds can readily provide more negative than positive attributes, (that's why I can write over 100 pages in my Management Engineers MIG book on pulsed issues). And for all of you that invest $6000 for pulsed equipment because it produces miniscule amounts of weld spatter, well the bottom line is the $2500 durable, easier to use traditional MIG equipment can also produce miniscule amounts of weld spatter if you invest $60 for one of the MIG process control books available at this site and learn to control the process.

Metal cored MIG reality.
In the last decade I have never seen a carbon steel weld made with a metal cored wire that could not be made at the same speed or the same weld quality with a much cheaper MIG wire. Weld reality, I guess that when it comes to welding technology in North America, "salesmanship rules the weld shop"


The Most Improved USA Pulsed Power Source is ..... ?

If you have to succumb to salesmanship and purchase a "pulsed power source" for traditional carbon or stainless applications consider the "Miller Invision". After numerous electronic changes from its messed birth as the Maxtron to its electronically reborn (many times over), again Invision, Miller has finally got this one right. However with all its improvements this power source offers weld benefits on very few applications.

When it comes to traditional MIG welding transfer modes the Invision is inferior to the lower cost more durable pre-1999 DeltaWeld. In over a 1000 manufacturing companies I have attained weld benefits only twice from pulsed MIG on carbon steel applications, both applications were very sensitive to miniscule amounts of weld spatter. My advice, don't use this or any other pulsed power source if you can do the job with traditional short circuit spray, or flux cored.

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