Made a fixture and did some gas welding... 4130.

tacking...

tacking..

Welded. I'm a little out of practice so my bead is not as nice in appearance as I would like. But after a couple more I should be back in the swing of things.

If I may, what are you up to? What secret bit of captured UFO technology are you trying to integrate now?

That is what I'm talking about! I got my gas setup last month and need to find a class to get going. I took a class 10 years ago but at the time I never invested in an Oxy/Acet outfit. I did not enjoy Mig or Tig the way Gas welding felt. What torch are you using? I picked up a Meco Midget to get myself started.

Iffen I tell ya I'll have ta Keel ya...

What I can say is I will be holding a contest soon.

Just a Radnor which is a Victor junior knockoff. The tip is a 1 the filler rod is ER70S-2 tip filler. 4130 was engineered by the aircraft industry to be gas welded. Guys tig it now most of the time but the theory is the tube doesn't preheat properly to return to "N" With gas welding the tube tube heats slower and the heat extends further down the tube creating a charge in the tube that enhances or delays cooling. This allows the weld to return to "N" under natual cooling. I added a heating device to the fixture in the form of the solid bar stock. It heats and holds the parts in a heated state and allows slow cooling for a strong joint.

You being in N. Jersey (industrial area) there should be plenty of places to

take a welding class. Community colleges often offer classes that could get you

rockin. But first, what are you going to be welding? Oxy/acc is great for heavier

materials, brazing and non ferris metals. Sheet metal can be problematic

because of the heat , it has a tendancy to warp the metal your welding. If you

are going to use your new found talent to restore your car (sheet metal) IMHO

you should learn to use a mig. It is pleasenty easy and creates a lot less heat.

Rick,

For highly stressed joints, I would TIG weld to attain better control of the bead followed by annealing with a torch.

Good luck; practice will get you where you want.

Andys

Gas welding is my absolute favorite method. I asked about doing 4130 with it, but no one really knew anything about it.

I like the fact that the torch takes care of preheating the surrounding area as part of the process. Several companies have now said preheating isn't necessary and that 4130 tubing can be mig'd like normal steel, but I don't like it. Most Nascar teams just mig it like mild steel, but they are so over designed that it doesn't matter for them. In a huge wreck a whole corner joint will break out several inches each side of the weld from the lack of proper pre/post heat, but an accident of that magnitude is fatal, so it doesn't really matter.

I'm pretty good with gas, but it takes a ton of practice and it's been a few years. A nice gas bead looks like Tig. This is from a practice piece I did few years ago

I see your points regarding the advantages of Mig but I am determined to learn it. I do not have a 914 yet and want gain my metal working skills first. Time is on my side and I will see if I have what it takes. I love all the projects that get going here. Thanks guys.

Actually, for body work gas welding is about the best there is. Have you ever tried to metal work an area that's been mig welded? It's hard as a rock.

With gas you have a larger heat affected zone, but the temp is just enough to develop a weld bead, no more. The metal stays soft and thus much easier to work afterwards. An area repaired with gas welding can often be worked to near perfection needing little or no filler.

I recently used a stud gun to try getting some of the dents out of a 914 floor pan. It worked pretty well, but the heat from being welded was so high that the metal became much much harder to work than it had been. Mig has the same effect.

Nice Job ...

I'm a fan of gas too ...

I've been using it a lot on my patch work ..
The key seems to be good fit up .. I can get by with little or no filler ...

Very nice work Steve.