Hi Ryan, I said if the pieces are tacked together at regular intervals, you can weld long beads. The regularly spaced tack welds hold the panel edges. The only place needing stretching is the weld and the blue area on either side of the weld, so it does not matter when you do it. You can treat a long gas weld just like a shorter weld. Stretching is easy, smoothing is easy, shrinking is easy. Checking contours in all directions is easy, and picking up minor low spots in the area you have worked is easy. Anyone with the guts to try gas welding should be able to learn how to do this with some practice. No magic is required. Most people starting out lacking the confidence to take the techniques far enough and fear hurting the metal. Many of the skills that help a person dent repairing and metal-finishing can be used for making gas welded panels straight. I first tried doing longer gas welds after watching a Kent White video in which he welded a very long section of a grill surround WITHOUT stopping to stretch the weld every 20 seconds or so. I tried this on the fender flares I used to make, and it worked very well, saved a lot of time. This taught me to be less cautious, and more confident. Sometimes if you try something that is not accepted practice, you learn a better way. There are many things this applies to; manipulating sheet metal to form rolled shapes by hand, hammer and dolly work, shrinking, stretching up low spots etc. An example of this is stretching up low spots during metal-finishing. The conventional wisdom says that you hammer on dolly to stretch the metal up. This is true and will work beautifully. An easier way for a beginner is to use a ballpeen hammer from below, watch for the tiny little bumps that show up in the low spot, then smooth with a hammer and dolly. Very simple, and effective. Slightly more intuitive than hitting down with a hammer to bring metal up : ) It is an important part of the learning curve to replace hesitation with experimentation. Knowing that the metal can be rescued from almost anything you do to it helps a lot, and sometimes fixing mistakes is the best teacher of all. A welded joint is simply an area where the metal has thickened slightly reducing surface area, and pulling on the adjacent surfaces. This causes warping away from the weld. The warped area will usually pop back once you have stretched and smoothed the weld area. If it doesn't, go into dent repair mode and bump it up with a smooth dolly or ballpeen hammer, smooth with hammer and dolly, shrink if required. Lather, rinse, repeat : ) I show these metal-finishing techniques in my youtube videos below. All it takes is practice and a lack of fear. Also look for David Gardener's video on gas welding on youtube. Very nice stuff. John www.ghiaspecialties.com
Here is David's video on youtube: http://www.youtube.com/watch?v=IGElSHzm0q8 John www.ghiaspecialties.com
Thank you John for posting a link to my youtube footage. Just found this thread and thought I would add my two penneth worth (that's English for 2 cents worth) Anyway when Gas welding steel panel sections together I use the traditional coachbuilding method of joining, this involves tacking the sections together using no clamps, I tack every 3/4 of an inch at least, starting at one end of the joint and ending at the other, I then plannish the tacks and run the weld in starting at one end (the right hand end of the joint if you are right handed) and run the weld to the other without stopping. I use no filler rod and because the HAZ is very even little distortion is caused, the HAZ is very narrow because you can move very quickly along the joint. It goes without saying that the joint has to be very accurate but this is not hard if the right approach is used in the preparation stage. The above method is the way that it was done in the early days when most car bodies were hand made (in England at least) I have restored wings from the twenties which have been welded in this way. This same technique can be use with tig and in fact this is the method that Contour Autocraft use and teach. I prefer to gas weld for the most part. The only down side to this method is that it leaves slight undercuts in the panel but as most steel panels are painted a little stopper or just a few coats of primer will sort this out. David Gardiner
Just thought I would post a photo of some gas welding done by my employee James in the way I describe above.
Great thread. I've gained a lot in the reading. Going to try out the small torch I bought at a swap meet last month. Couldn't find it listed in the Victor catolog. Now I know why. Its a J27. The seller didn't know what he was selling and I didn't know what I bought. All I knew was that it was Victor and I was looking for a small torch.
I know it's an old thread, but the information is still good. This is my new torch, set up with a 00 tip. I'm running 5psi and 3psi I turn up the acetelene just past the soot to where it starts to flicker I turn the Oxygen to a sharp cone then back it off a little. The pictures are top and bottom, I don't seem to be melting all the way through, am I going too slow, possibly not hot enough??? Help.
I'd try slowing down a bit and welding it without any rod unless you blow through. I've been practicing David's method for a few months now and have been really happy with the results. cool torch!
Hey, I'd suggest you try two things : First, you may try some more heat. Whyle it's true that your gauges read 5&3 psi. they may be somewhat less. Most of the bigger regulators aren't very accurate at low pressures & unless your gauges are new or in great shape, they may not read accurately. Second, try to slow down with the increase in heat. Are you welding with a good healthy nertual flame? " Spending a nation into generational debt is not an act of compassion "
We just finished the oxy/fuel welding portion of the welding program that I am taking at our local trades college. After being shown the proper way to use a torch and the different types of welding, fusing that can be done it really gave me a new respect for the lowly little torch. I have a dozen or so cars that I have sitting around waiting to donate parts for future builds and I am thinking I am going try and do some metal resurrection on a couple of them using the oxy/fuel method. Watching the videos and reading other gas welding posts has really got me excited about trying out this tried and true method!
I thought i was screwed being my new shop doesnt have 220 yet to run my mig, and all i had was my flux core 110 lincoln, but that was almost a year ago and i still dont miss it at all. I picked up a 00 and i can weld anything, i'm not gunna go back to mig other than production crap. One thing over looked, make sure you have some decent hammers and dollies for hammering the welds, atleast comfortable. The big advice i have is PATIENTS is key, every screw up i made it because of crappy fit or getting ahead of myself
Found another small torch at a swap meat last weekend - a Alex. Milburn. It came with three tips a 000 - 00 - 0 - 6 . The tips look a little like Victor's. Bought it and the Marcuette?? lite jet cutting attachment. These little torches are out there. All of these were found at swap meets in the past year. 1) Victor J27 2) Airco 0400 3) Alex. Milburn A1500 4) National NO. 30 5) National Koolite 6) Marcuette Lite Jet 22-111
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