Another welding rig question

[Matt@RFR]

Hell, they're rated to 1/4" plate, but I wouldn't do it. Not on anything structural.

With my 251, I'm running 17.6 volts and 258 ipm for 1/8"-3/16" mild steel with .035" wire. That's right at the top end of the 135 machines. Plus, the 251 is at 100% duty cycle at that setting.

I think the 135's can do 3/16", but I really think that it takes careful weld prep to get them to do it right.

I was out in my shop, and for some reason this statement of mine popped into my head. I need to clarify this for my own piece of mind.



The stated setting is what I weld our crossmembers and rear ends with. Those parts are made up of .095, .120, and .188 mild steel plate and tubing. I weld all the .095 joints first, and the .188 joints last, working the progression from thinnest to thickest. This lets me use a too-hot setting for the thin joints (albeit moving quite quickly), and pre-heats the thicker joints, allowing a slightly colder setting.

If I were to run a 3/16" to 3/16" joint first, I would be running more like 18.5v and 275 fpm, or thereabouts.