I recently purchased the spool gun without checking compatibility with MIG machines. Oops- mistakenly assumed it would work on my relatively new SP-175 Plus with the adapter harness. After some examination it is clear that the gas hose will plug in and a 4-pin Amp connector can be retro-fitted without a problem. The machines recommended for the spool gun obviously have a new circuit board design and socket connector layout different from my SP-175. The spool gun switching harness will absolutely not work on my machine without modification. At first I thought a simple SPDT toggle could be used to redirect DC current from the internal wire-feed motor to the spool gun motor, however, they have used a DPDT toggle to open the main motor circuit and close the spool gun motor circuit from a different power pin on the CB. I wonder if this is due to different motor speeds required for the spool gun. Has anyone out there successfully performed the hack to make this combination work? Not wanting to go buy another new MIG.
Chuck Jensen