As a welder using the MIG for over twenty five years I have to dispute this statement.It is all about technique.The TIG requires good control with two hands and a foot to get it right.The MIG just requires experience and good pool control.It is fast and doesn't put so much heat into the whole structure that it will distort.There is nothing that a TIG can weld that I can't with a MIG and I can do it twice as fast. Cheers RossTIG can do any weld and any material better than MIG anytime, it is just slower.....
I agree, that there is nothing that TIG can weld that MIG can´t weld... TIG have just better overall quality for welding seam. TIG have better penetration control, especially thin wall material than MIG. You can weld more precise and smaller seam with TIG. Aluminum welding TIG will make better and stronger seam than MIG, even better than modern pulse MIG.The MIG just requires experience and good pool control.It is fast and doesn't put so much heat into the whole structure that it will distort.There is nothing that a TIG can weld that I can't with a MIG and I can do it twice as fast. Cheers Ross
While I agree with all you say,the Tig does a beautiful seam weld the same can be done with the Mig. Heat control is controlled by two things and this important in thin material. First way of heat control is the normal amperage setting,the thinner the material the less amps. Now the second control mechanism to control heat is the amount of wire going into pool,the more wire the cooler the pool.To weld thin tube with the MIG requires low amps(small pool) low amount of wire feed (hot weld) and one has to be brave and move fast.This will produce a full penetration weld.As with TIG the size of the bead is a result of wire input and since the MIG wire keeps coming then the the bead and the heat can be accurately set. Cheers RossI agree, that there is nothing that TIG can weld that MIG can´t weld... TIG have just better overall quality for welding seam. TIG have better penetration control, especially thin wall material than MIG. You can weld more precise and smaller seam with TIG. Aluminum welding TIG will make better and stronger seam than MIG, even better than modern pulse MIG.
MIG is fast. It can weld good aircraft quality seam....but it will add lot of excessive material in that welding seam because nature of MIG welding method.
There is no way to weld same or better quality seam with MIG if use same amount of welding wire like TIG. If welding method need to use more wire to achieve same strength, it cant beat one that use minimum amount of material to do same job.
I have lot of practice for both methods, steel, stainless steel and aluminum, and both are great ways to do the job. I prefer to weld TIG always, if job is requiring high precision and quality.
If you are a beginner then start with Oxy.Learning to control the pool(puddle to you northerners) is easier with the oxy,heat control being instantly changed by removing and putting the flame in and out.MIG takes a lot of process examination to weld something like a 4130 fuselage. Each cluster and each part of a cluster needs different amounts of amps to make a good weld. Aviation welds are suppose to be 100% penetration; most MIG welds are not, or at least most users cant get 100% penetration. American Champion and Kitfox went through a bunch of growing pains because of MIG. TIG and OXY/AC are, within a range, adjustable on the fly, so changing thicknesses and groups of tubes can be handled without stopping. It is part of the skill that is learned when welding. Although Titanium can be welded with MIG, there is probably not 100 people in the US doing it. Most would pick TIG for Ti because perfect is more important than fast. If learning from scratch to weld, OXY/AC will teach you everything; if you are really into welding you can pick up the process you like. Like a musical instrument once you master one, adding a different instrument is no big deal; just learning the quirks.
I think that is correct -- or at least I hope so -- mine is clearly made in China... I would have liked to stumble on a Miller or Lincoln, but after watching for some months, the deal never popped up... in my case it was noticeably more than $300, but still less than four figures -- the straight DC TIGs are quite modest (HF lists one), but I am primarily planning on some aluminum so needed AC as well... the good thing is that most metals used in our homebuilts don't require very high amperage because the metal is so thin (heck, I'm still operating mine off 110 volt as my 220 volt plugs don't match -- yet), so there is little requirement for the mega machines... of course with the weekend-warrior specials you do give up some features, pulse would be nice... but the basics are there, and if one is comfortable with gas, I haven't (so far) found the transition beyond what I expected -- actually pretty nice... although I'm not yet practiced enough that I'd consider my practice welds airworthy...one of those cheap Chinese TIG. Cost less than 300$. Builder who build one or two planes in his lifetime don´t need fancier welding machine like that.