I found that cheap a$$ harbor freight wire feed worked great for my cab corners and other light gauge needs.
Its so dirty that all I could do is hit one spot at a time and then while I'm wire brushing and cleaning the surrounding area getting ready for the next 1 or 2 second session its cooling down
On the plus side I worry very little about too much heat build up and warping... on the down side I go through wire brushes a lot faster....
