Carbon arc -- now what?

I use mine for brazing when I have a large object. Lots of heat, fairly gentle flame, doesn't burn the brazing rod. I bought it years ago when I didn't do enough work to justify a O/A set up with the retal fees on the tanks.

I've never tried welding, I might try a one carbon version as an experiment.

The old timers used to deal with stuck truck lug nuts us> Anybody have experience with a carbon-arc torch?

That's what I'm thinking ...

Aha--I guess I need to dial it down. I tried to hold an arc at 75 amps but couldn't ... but didn't try too hard, and didn't have the two carbons. How quickly do your electrodes consume? And is the end cone-shaped?

Yeah, that's the kind of thing I'd like to be able to do. I hadn't thought about trying to weld with it, since I would normally just use a stick electrode :)

Carbon rods are usually copper coated and used with compressed air in "arc-air" gouging of defective welds. Compressed air forces the molten steel away from the arc, the process makes short work of shifting large amounts of steel and makes a hell of a racket.

Yes, I know about the air gouging system; what I'm referring to is somewhat different. Apparently it used to be quite common to have a carbon-arc torch to go with your buzz box for heating metal, but it's hard to find them now, or at least I haven't found anyone locally who sells them. I think the gouges may be more commonly available now than the torches.

Andy

I have a couple of them around. Work good for brazing when you know how to adjust them. Also using one electrode you can do spot welds on sheet metal easily. I use the copper covered rods and have no problems. Eastwood still sells a spotweld gun that uses carbon arc electrodes. They work pretty good if you cannot get to the rear of a panel with a tong style unit.

To use a carbon arc torch you use two electrodes and adjust the tip angle to adjust the "flame". The sharper the angle the farther out the arc will reach and put more heat onto the work. The shallower the angle the lower the heat onto the part. One word of warning though the arc flash will cook you worse than standard arc welding and it reflects a lot of heat back. Also don't forget that you have both sides of the circuit in the torch, set it down CAREFULLY.

I have a carbon arc torch somewhere around here that I bought at Montgomery Wards, back in the day when they were in competition with Sears in the tool department, And there were no places in the American heartland such as Northern, Snap-On, NAPA, Enco, MSC, Grainger's, or Harbor Freight. I would guess late '60's or early '70's was when I bought an AC buzz box welder from them. I just threw this buzz box on the trash pile a last month, it still worked, but the case was about rusted away, and it probably wasn't real safe, besides I finally bought a new AC/DC welder..

It came with two electrode holders. One was a single electrode holder that you could use regular rods with for welding or a single carbon rod for gouging, brazing, or spot welding. The other electrode holder held two carbon rods, one on each leg and was used for heating items. The legs were moveable, were spring loaded and the tips would come together something like tweezers when you squeezed the handle together. First you fastened the carbons into the tips and adjusted them so the tips were about an inch apart, IIRC with the angle set narrow for a long arc and shallow for a wide arc. You would strike an arc by squeezing the handle to bring the two tips together. The arc was really bright, and there was a little dark smoke, and a slight dark residue (burnt carbon?) would be left on the items heated or welded. The carbon rods it used ranged in size from about ¼" to ½" and would last several hours. Carbons were considered non-consumable electrodes but they were consumed but at a fairly slow rate.

Hmmm -- I'd seen this in the Lincoln catalog, but whenever I've looked at any of the on-line welding supply catalogs, they don't seem to carry it.

Anybody ever made a home-made torch?

It's not apparent from the picture but there is a thumb control that allows you to start the arc without touching your work then allows you to adjust the arc to suit your conditions as well as compenste for the slow burn off of the carbons. I tend to run mine fairly hot, my carbon life is not great. Perhaps 20 to 30 minutes on a pair of 6"x 3/8" carbons.

The L> Hmmm -- I'd seen this in the Lincoln catalog, but whenever I've looked at

Just happened to run across this site:

Bert

RoyJ wrote:

Bert, these are AIR-carbon torches, very different animal. These are for scarfing, not at all what the OP seeks. - GWE

Bert wrote:

Yep -- this just illustrates what I have found to be true. You can get the gouging torches, but the carbon-arc torches must be a special order.

I've had one or two offers to sell one used, and I may take someone up on it. On the other hand, Roy just answered one of my questions -- I wondered if the electrodes were the same for gouging or for the torch. Maybe I'll just get some electrodes and see if I can rig something up. Even if it's just a q&d kludge for now, that will give me a chance to see how much $$ I want to put into this ...

Thanks to all for the help and info!

Andy

Head to your local welding supplier and pick up some 3/16 or 1/4 inch gouging rods, they work great for carbon arc welding.

Actually had to try this process during my weld tech program. You can aslo use a hydrogen shielding gas " Atomic Hydrogen Welding"

You will have to find a copy of the AWS hand book, Volumne 3, prior to version Seven. Three or Four would be best for in depth explanations of both processes.

John

I forgot one important point; remove the copper coating for best results.

John