Montgomery Ward Power Kraft 230/140 AC/DC shunt adjustment fix (with pics)

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In my quest to teach myself how to weld, I'm always scouring Craigslist for used equipment.  Some Chucke2009 videos had me wanting a DC welder.  I currently have a Miller Thunderbolt 225 that was made in 1977, a Lincoln Power Mig 140C and now a Power Kraft AC/DC arc welder.  I purchased it from the original owner's son, who had it wired directly into his panel with about 20' of 12awg wire   That should have been the first hint.  Well, I ran a couple of rods with it at his house and it seemed to weld fine so I loaded it up and brought it home.I installed the correct power cord and started burning rods.  After welding with it for a little while, I noticed that the shunt didn't hold the amperage setting I selected.  I did a lot of research on the web and it appears that this is a fairly common problem(not a great design).  Some work arounds were listed, but if I couldn't get this thing to work right, I was going to cannibalize the DC output section and adapt it to my Miller.  After inspecting it with the cover off and seeing how the shunt clamp worked, I noticed that about half the time, the tension spring and washer assembly would slip between the phenolic struts.  When this happened, insufficient clamping force was applied which allowed the shunt to slide down when the transformer vibrated.  The other side of the spring had a nice little bracket that kept this from happening so I fashioned  a similar one out of 1" tube steel, ripped in half with a slot to go over the tension rod (gray bracket on the right side of the spring/washer below).  I made sure that it couldn't fall off when adjusting the shunt.  Now it holds whatever amperage I select and welds great.  Well, it burns rods just fine.  It will weld great in the hands of a real welder.  Hopefully this post will help anyone else that has one of these welders.
Reply:Welcome to the forum!Nice machine and good post! Someone will find it helpful one day.GravelThe difference between theory and practice is that in theory there is no difference.
Reply:Thank you. I figured after all I've learned on here, it was the least I could do.Here's one of my first DC 7018 passes.  (top one- ignore the blob fest)Last edited by donkengine; 05-20-2014 at 11:13 PM.