Big 40 Gas connections for Suitcase?

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I have a 1981 Miller Big 40 gas generator welder and recently acquired a suitcase welder to use but cannot get it to work.  I don’t know what I am missing, but realize that most of the posts who have the Big 40 and have been successful in doing so have the diesel model.  I do not have the CC or CV connections like I saw in another post regarding connecting a suitcase to the Big 40.  Is this required, or is there a work-around I can do in order for the 8VS suitcase to work directly with the 1981 Big 40 gas welder I have?  (It is not the upgraded 7.5Kv model from the factory.) I should also clarify that I have 1/0 cables running with quick connects, and the suitcase came with a 1/0 cable with the Miller 3/0 to 4/0 male connector on it (wrong I know), but I was told that it would work fine by local Airgas salesperson.  All other quick connects are not Miller branded, but I have the connector to allow that 1 Miller (50 series, part #241345) into the ‘generic’ quick connects.  The Miller Big 40 should have ample power to supply the 8VS; however, everything I have tried doesn’t seem to work.Any help would be greatly appreciated.Last edited by Newelding; 3 Weeks Ago at 11:12 AM.
Reply:Your 8VS has a switch inside for CC/CV. You will need to run it on CC. You cant do short circuit mig with it. You can do spray transfer in the flat position, but it's really hot and fast, best for over 1/4" material. You also need 90/10 of other high argon gas.You can also do flux core, or dual shield with good effect, tho it will also be pretty hot and fast welding.If you have the machines hooked up right ,dcep for spray and dual shield, electrode negative for flux core, you will want to run a fairly high wire feed speed.It will take some time to get the output settings on your Big 40 right, try something in the middle and go from there, probably around 160 amps is a good start point.I run a 8VS off a AEAD CC machine.
Reply:

Originally Posted by Poleframer

Your 8VS has a switch inside for CC/CV. You will need to run it on CC. You cant do short circuit mig with it. You can do spray transfer in the flat position, but it's really hot and fast, best for over 1/4" material. You also need 90/10 of other high argon gas.You can also do flux core, or dual shield with good effect, tho it will also be pretty hot and fast welding.If you have the machines hooked up right ,dcep for spray and dual shield, electrode negative for flux core, you will want to run a fairly high wire feed speed.It will take some time to get the output settings on your Big 40 right, try something in the middle and go from there, probably around 160 amps is a good start point.I run a 8VS off a AEAD CC machine.
Reply:As mentioned it will work in spray transfer and that won't be ideal. All you will have on the machine is an amperage setting, both coarse and fine on the dial. The wire speed settings on the 8vs should take care of itself to some degree. Make sure the " jumper wire" work clamp connection is intact and in decent shape as that is what senses the arc and allows wire to feed . I believe you will need to run the engine drive at welding RPM when using as the electronic idler solenoid won't be able to detect an arc to increase RPM.
Reply:If you open your 8VS, there are 3 switches above the rollers, one is for selecting CV or CC. Use the CC setting in the suitcase. It also has high and low -low is 25 to 200, high is 100 to 800 ipm. Use high. I just leave soft start on.