Ipm

[performance]

The original specs we expected for the units were to be within the 500-600 ipm range. Also, for a .023 drive roller... As people can see, its standard with an .030 minimum. What is at the heart of the issue is that the larger wire sizes do not require the same wire speed as the smaller diameter, and the drive mechanisms are manufactured by Binzel, or a licensee of it. The maximum voltage they are rated for is 24V...They will not turn faster than the 24V allows when the rheostat is turned wide open. The factory states that there is a 10% allowance for wire speed roughly on either side...But within the limits of the .030 minimum wire size, its fine for operation, but not for .023...And the reason its been like pulling teeth to get the .023 drive rolls from them I suspect. As for aluminum operation and the spool guns...It seems that .035-.040 aluminum wire is what is necessary to use as well. We are working to see the maximum wire speed we can get out of the current drives without changing them out. It seems the target wire speed is somewhere around 350 ipm...When the factory gives us a spec it comes to us in Mpm. They don't get hung up on a tenth or two..which to us seems like a lot of ipm when converted, but when you are talking a larger, meter unit, its not significant. FWIW, we originally verified the wire feed speed much higher than it is now, but my proto unit probably had been a little different feeder too from some of the production units.

I want to emphasize that the MIG welders DO work well and that you will be hard pressed to find anything negative about them. Arc stability, controllability and overall function is unsurpassed. If your comparing only the wire speed, remember, the little 140's and 180 units offered in the price range similar to ours that offer 600 ipm or so, start out offering a 2 lb roll capability, and .023-.030 wire option and about a 10% duty cycle or less at maximum amps. We offer .030-.040 drive rolls which will handle up to .045, which require less wire speed to get the same results.

Additionally, I'd add that for those thinking they MUST have the .023 wire, have not tried the .030 yet. I've welded quite easily 20 gauge material with the .030...

While we're talking MIG, I'd also like to put a bug into some peoples ears about Gas selection for these units. I have used both 75/25 and an airgas proprietary blend of c18. Both weld fine, but, if you've never tried a lower percentage of CO2 in your mix, you will whip yourself for not trying it earlier when you do. Other companies have an 85/15 and some and 80/20...But the experience of a higher argon content will change many peoples view and enjoyment of MIG welding.

[DaveO]

I understand the purpose of the inert gas as a shielding agent, but not the chemistry or metallurgical contribution of the gas (if there is one). What is it about the argon / co2 mix that works so well in a MIG context, where straight argon works for TIG in some cases and helium in others?

Perhaps a link to a reference is in order... unless there's a really short answer...

[performance]

CO2 isn't inert. That's the problem. Its a slight oxidizer but far better than pure oxygen and it is heavy so that it sinks and collects around the weld so it "shields". Its ok for shielding, though you do get some contamination while mig welding with CO2. I have welded with 100% CO2 and its nasty stuff...In fact I learned to MIG in school many years ago on old Miller MIGs from the 60/70's with pure CO2...and the welds were full of spatter and far from shiny. It welds hotter, but its not any fun at all. However, with TIG, the tungsten is consumed because tungsten is rapidly oxidized in the presence of CO2. It just won't work. Helium and Argon are Noble, non reactive gases and offer good to excellent protection. Helium is lighter than air, so it has its draw backs when mixed.

Geezer, the I MIG 205 should have a faster wire speed.

[DaveO]

Thanks, Mark, and sorry for the delayed response: I'm traveling, been away from computers for a couple days.

If co2 allows contamination it seems counterintuitive to include it as part of a shield gas mix with argon for MIG. Is it another property, perhaps the hotter weld you mention, that makes it worthwhile?

[performance]

Yes, and according to some training texts if I remember right, it helps stabilize the arc when mixed with argon.

[Ram48]

Geezer, the I MIG 205 should have a faster wire speed.

Mark What is the correct Maximum IPM wire speed for the I mig 205?

[performance]

What you posted should be about right for that unit...currently.

[Ram48]

What you posted should be about right for that unit...currently.

Geezer, the I MIG 205 should have a faster wire speed.

Mark now you have me totally confused.
How can it be about right and have a faster speed at the same time?
I admit I know very little about these things but now I am totally in the dark.
Please bring me up to spreed on this.
Ray

[performance]

The recorded wire speed that Geezer posted is about right for his unit at about 400 ipm as the units stand now...