I am resurrecting an old MIG I made by Chicago Electric, I got it free. The voltage selector switch is no longer available. The switch was labeled from left to right 2 , 1, OFF, 3 , 4. There is a diagram on the front of the machine showing thin to thick materials showing switch position 1 as the thinnest and finally position 4 as the thickest. I am using a SPST and two SPDT 20 amp toggle switches to replace the old cam type selector, this way I get an actual off switch. The original cam switch is badly burned and would not operate correctly nor could I figure out its operation because somebody else had been inside befor me.
Now to the question. I need to know if the output voltage of the MIG gets higher as the material to be welded gets thicker? OCV readings go from 27.3 to 46.6 depending on the switches. I am thinking the lower OCV should be labeled 1 or Low and the higher OCV should be 4 or High, does this sound correct? Maybe use A, B, C and D with A being lowest. This is one of those "hard to get it right in your head" things.
Anyone know how to make a "HOT" mig gun cold? I know I could use a contactor in the ground circuit but I am not sure of the contact amperage with the D.C. voltage levels. The specs say this thing outputs 28 to 84 amps, but the specs also say the OCV is 22 to 34 volts, I would think these are "typical".
Finally, anyone know what brand the mig gun is on these old Chicago Electric machines?
Thanks for any help.
Thor