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Old 07-28-2009, 08:17 AM
David Gardiner David Gardiner is offline
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May 2009, Jan 2012, Dec 2014
 
Join Date: May 2009
Location: England
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Quote:
Originally Posted by jhnarial View Post
David

It is a slow process about an hour a foot.As you know If you hammer on a mig weld it will crack.So you have to keep up with it on every 3/4 of a inch of weld,there is hardly any hammering

If all you have is a mig welder it will work.Not the preferred method but sometime you have do what you have to do.

I have moved on to tig know but still use the same method.
Dont get me wrong Johnny I have nothing against mig welding, and I said that if its all you have Ok. I do think you made an incredible job of this wing but I know how much effort went into the welding and finishing of the welds. I feel that mig welding is not the best or quickest method for butt welding edge to edge because it takes so much effort to dress out and because the weld is harder that the parent metal it can crack once you have groung and filed it and hammered it. (or even once it is on the car and painted) I use mig for some jobs because its ability to join the panels without putting much heat in is what I need (for example a corner butt weld on a panel or for plug welding)

Tig welding is fine and I know that contour autocraft use tig and teach this method. I also know that if you dont use filler rod there are some issues with tig welds cracking, if you do use filler rods and you can get a perfect weld with very little penetration and build up of bead you can get a result that is easy to metal finish. The problem I see is the amount of skill it takes to weld to this standard with tig on thin sheet. The gas welding method I show on my DVD takes very little skill and can be learned with a few hours of practice, the resulting weld has very little build and very little penetration so there is no grinding to do, the HAZ as you call it is very even so little distortion is caused. The weld has the same properties as the parent metal and is the same thickness so it is easy to dress out. I think for someone who only has a mig your wing will be an inspiration but for anyone starting out I would allways recommend getting gas equipment, it is the most versatile method of welding (for bodywork on old cars) it can also be used to heat things cut things and it costs no more (over here at least) to set up for gas than for mig. Having both is ideal though!

Regards

David
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