I have done all of them and all have good and bad things about them. for most general stuff a small gas unit is great. The MIG is tricky on thin wall until you really know what you are doing, it's easy and inexpensive but takes a lot of practice to get a really good weld. But the best by far is TIG, you don't heat up too much metal, you keep it right where it needs to be, but it is very expensive. The Argon gas alone cost me nearly $250 alone just to weld my Acro Sport II fuse together.. I finished it with a my Smith gas welder I picked up at OSH. The Gas puts a LOT of heat into the metal warping it and changing it's temper.
For me it comes down to preference and expense. If I could afford a TIG I would, but for now I stick to my gas for small jobs. Also on fuel tanks, I had an old codger that worked for Harrah's automobile museum teach me how to braze (solder) my tanks together and they are nearly as strong as welded.. Fred Johnson Reno, NV All I have been reading alot about the different methods and looking at welders and reading alot about techniques before I try to weld my aluminum tanks and 4130 control stick. It looks to me like MIG is ok for aluminum if you use a spool gun. Gas looks a little trickier but do-able with flux. Any one tried MIG? If not why not. I know I can do it all with gas but just exploring other options before I plop down a bunch of money. TIG is out for me because of cost. Craig
