Tim, the aluminum wiring has an issue that it is most critical that you
understand. When aluminum gets hot, it expands more than copper. So much
so that after a connection has been made, used to warm, then cooled, it will
get loose because the aluminum flows out of the connection. This poor
connection now creates heat due to the resistance, which starts it all over
again. Eventually a fire happens. The NEC is very concerned about the
history of this item, and has specific rules that you can't get away with
skipping.
Use connections that have "AL-CU" stamped on it and no others for that
connection. It is wise to buy a bit of antioxidizing gel, like NoAlox or
similar, and fill the connection before you assemble it with this gel. It
keeps the dissimilar corrosion away, which makes the fire issue crop up
again. Hey, it isn't inside the walls of your house, but nonetheless I
don't think you like any unnecessary action going on, even more so in a high
current connection like a welder.








Its in my house. Apparantly , in the early 70's the bldg folks here in Arizona
got real stupid(or , more likely, had their pockets lined)and they allowed
aluminum wiring in many housing developments , including mine. So far, in the
last 5 years that I have been here, houses go up in flames about 1 per year. I
oxguarded all my outlets but I have still; had three produce smoke and the one
on my patio only works in the rain. I also eat light bulbs like nothing you
have ever seen.Even the miser type bulbs. What bs. Thanks Az. Heed any warnings
folks give about aluminum wiring. It sucks and is probably more dangerous than
terrorists on a plane.
MLM