MIG vs. TIG

Originally Posted by Madav8tr

Hopefully they have hired inspectors that know what they are doing since the early 70s. The weldor that did that is as good as any you will find. Follow the link ans read a little before you dismiss that as a poor weld or even a mig pulse weld. The man has skills

I'm sure welding has changed as much as everything else in the last 40 years. There's really no way to tell by looking at the welds up above as to how strong they are. The rule of thumb used to be if you welded two pieces of steel together, then forced the part to break, that it shouldn't break along the weld. The weld should always be stronger than the metal.
I'll take your advice and check out the link.

OK, ZTFab is an artist with the MIG welding. It looks completely uniform. It was also nice to see some beginner attempts to compare the pro jobs to. One guy mentioned that ZT didn't have any splatter balls and was answered that his voltage is probably too high. ZT has been to school and can more than likely handle TIG without any problems.

What I don't get is the individual dimes bead. I think that those MIG welds will be left as is and painted or chromed over as part of the look. A TIG weld is a procession of small 'V's and doesn't add but maybe a 1/16" thickness to the surfaces at the seam.

If the MIG welds are going to be ground down, that's a lot of wasted wire. That's why I think that they are ornamental. I like the look myself. I could see doing Pick-up cattle guards like that.

I know this is an older thread, but here is a youtube channel that has some great beginner videos.

http://www.youtube.com/user/UCITLTC

D0gbreath, the only reason I posted the link above was in reference to the comment about how MIG welds were only suitable for production work and that MIG isn't an option for someone that desires a nice looking weld. I simply wanted to illustrate that there are some really talented weldors that can make a structurally sound MIG weld that is also pleasing to look at it. Folks here, for the most part, simply believe that a TIG "must" be used if something is to be welded or the world will end. I don't buy that at all. I still wanna buy a TIG machine though if for nothing more than the ease of welding different materials with the same machine.

Originally Posted by d0gbreath

There's really no way to tell by looking at the welds up above as to how strong they are.

This is somewhat of a misconception in my opinion. No you cannot know the exact shear strength or tensile strength of a weld by looking at it. But if you know what to look for in a weld you can be confident in the strength of a weld. The old "I've seen pretty welds that are weak and ugly welds that are strong as hell" adage is bullshit. Either they don't know what a weld should look like or don't know what a weld should look like after destruction.

A good weld is more than just uniformity. There are many factors that make a weld "good" . Such as penetration, tie in to parent metal,and shape and height of weld. I have seen people say a weld looked good that had so much undercut in it that it was scary. When you do a destruction test on welds with significant undercut the bead itself usually will not break but the base metal will. That doesn't mean the weld was strong. It means the travel speed was too fast and thus deposition rate was not enough making the base metal around the joint weaker.

I think any process can be good looking if done properly. I would weld a frame with any process and have done so on vehicles that experiece much more stress than a motorcycle frame. I am no expert but feel that I have enough experience to know my limitations and am confident in my skills. Also if you want to see amazing welds there used to be a thread on Pirate that was amazing

welding is fun.... mmmmmgay.........

Originally Posted by Madav8tr

D0gbreath, the only reason I posted the link above was in reference to the comment about how MIG welds were only suitable for production work and that MIG isn't an option for someone that desires a nice looking weld. I simply wanted to illustrate that there are some really talented weldors that can make a structurally sound MIG weld that is also pleasing to look at it. Folks here, for the most part, simply believe that a TIG "must" be used if something is to be welded or the world will end. I don't buy that at all. I still wanna buy a TIG machine though if for nothing more than the ease of welding different materials with the same machine.

I only opened my trap because I've welded TIG professionally. I've also arc welded with rods for some biker friends back in the '70s. What I have never done is use a MIG welder, so I'm not really qualified to judge using that machine.