Mig voltage and wfs ... Per thickness?

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I'm a bit confused as to how to find the right voltage and wire feed speed for handling different thicknesses in steel....Is there a general rule of thumb? i know the miller calculator app does it for you.... but i was wondering if there was a proper formula?Thanks!!
Reply:What I was taught and it seems to work for me is to set it for 2inch/min for every thousandths of an inch metal thickness and then adjust the voltage for the bacon frying sound. So if I was going to weld 1/8 steel I would set the wire speed to 250inch/min and play with the voltage to get it sounding good. Sometimes on a machine without infinite voltage adjustment the wire speed has to be adjusted slightly to get it running just right but it will get you really close.My "collection":Homemade Stick WelderVictor O/A TorchAC 225Ideal Arc 250HF 90 Amp Flux CoreHF Mig 170Solar 2020 Plasma CutterPower i-Mig 140EHarris O/A torchHF Dual Mig 131140STAlpha Tig 200x
Reply:The proper way to setup the machine is set the wire feed for metal thickness, then tune the voltage for a smooth arc. Just like Iain P said. If it starts stubbing into the workpiece voltage is too low, if wire burns back into the tip its too high.  The miller welding calculator is good for flat/horizontal fillet joints, as far as I recall. For flat/horizontal butt joints in sheet up to 1/8", 1A for every 0.001" thickness is a rule of thumb, although I find i need to use less than this when gapping for complete joint penetration. As far as i recall, 105-110A/17V is perfect for 1/8" with 0.1" gap, 145-155A /17.5V for 3/16" with a 1/8" gap. For flat/horiz/overhead fillet welds I find Miller's app to be pretty good. For vertical uphill fillets, you'll likely have to turn it way down.There are rules of thumb about amps per wfs as well for different wire sizes. These assume linear curves and short circuit transfer. For more accuracy, you can find curves of amps vs wire speed for different wires and sizes in lincoln's gmaw welding guide.Last edited by Jieve; 07-12-2015 at 08:35 PM.
Reply:Thanks! I will give it a try.
Reply:Both methods above are poor ways to set a machine IMO, for one different shielding gas mixes, wire type (ie ER70S-2 VS ER70S-6), wire diametef, joint configuration, machine your using, stickout length and personal style all effect machine settings. The method is sainificantly different for a vertical weld to a flat T, and again for overhead, and for a flat butt weld, the above mentioned will be an okay starting point only, you need experiance to learn the ins xnd outs of machine settings, and id need weeks of instructing you to explain the most common variations of the above mention parameters, it took me years of trial and error to learn them, an i can only replicate them by feel while welding, no one will be able to remember each setting on each machine with each variable, and no calculator will accoug for each variableWhat i can advise is that personally, i tend to set my voltage to the joint configuration im welding (ie 28ish volts for 1/4 mild steel) and then adjust tg wire to suiteLast edited by ttoks; 07-14-2015 at 07:05 AM.