Some words of warning, based on my own initial experience with a 110v stick welder:
1) You will be limited not only to 3/32" rods, but also to 6013 or 7014. Both are fine for many things, but not for everything.
2) 100 amps on one of these little machines is nowhere near as "hot" as
100 amps on a larger machine. I found that I could weld pretty well on
1/8" material or thinner, but struggled to get a good weld on anything thicker. Of course, I was brand new to welding at that point, so I don't know how much better I might be able to do with it now ...
3) Rather than one of the HF machines, consider getting a Century (available at Northern Tool; also sold as/by Sears). The HF machines have abysmal duty cycles and very low OCV; the Century/Sears is not great, but it does have a 20% duty cycle at full output, and a slightly higher OCV.
4) If you can find some way to run a 220v machine, you will be much, much happier with it. A basic 225 amp AC machine can be had new for around $200. I understand not being in a position to run a 220v circuit, but if there is an electric dryer outlet available, that will work fine for most welding (it won't let you run the full 225 amps, but you're unlikely to need that).
Thanks for the info everyone. Actually, I can run 220V I found out. I have a sub panel in my garage. But, I'm not sure what breaker to use or if I can do this myself. I'm going to read the posting above about setting up a welding breaker.
And, if I'm going to the trouble of doing all that maybe I'll spend a little more money on a better stick unit or (with an evil grin creeping across my face) a TIG/Stick Inverter. Thermal Arc anyone?
We'll see. These things have a way of snowballing. :)
You would use a 2-pole, 220V breaker sized according to what welder you plan to use. A lincoln tombstone stick welder needs 50A and the Thermal Arc 185 TSW needs a 40 A. Hopefully you've got room.
The breaker gets installed so that it contacts both hot bus bars. It will have two terminals--one for each hot line (black & red). You would run a 6 gauge wire from each of these terminals to your NEMA 6-50 receptacle. You would also run one green or bare 10 gauge or larger wire from the ground bus in the subpanel to the ground of the receptacle. These wires should be protected by drywall or in conduit. 3/4" EMT is easy to work with.
The TA is a sweet machine. It is spendy, but also a lot of welder for your money. Don't forget about grinders, chop saw, bandsaw, etc...
Before you run out and buy some #6 wire and a 50-60A breaker check to see what wire and breaker is supplying your sub-panel. Putting a 50A breaker on a panel that is being fed with #10 wire and a 30A or less breaker is pointless since you are limited to the rating of the breaker feeding the sub-panel.
I have an old Miller 225 stick machine that calls for a 60A breaker or thereabouts. It is fed with #8 wire and a 40A breaker and it is just fine for my use since I hardly ever go over about 145A and am typically welding under 1/4" steel.