fixed my venturi burner

[evfreek]

For quite a while, I have been having a problem with my propane forge. It seems to have been getting weaker over the years, and I have not been able to figure out what is going on. I do all my welding now in a sold fuel forge, and it just seemed that the propane forge has just been getting weaker and weaker. When I use it to heat steel, the steel just seems harder to work. It still works, but seems to have degraded.

So, I decided to "take its temperature". There are a few ways to do this. First, I stuck a copper wire out of a scrap piece of romex in. This should melt immediately (about 1980 F). It did not. It slowly formed a ball, and dripped of the end, but very slowly. OK, it is about 2000 or more. That is why it still works. Then, I stuck a couple of welding rod stubs in the bottom, and tried to fish them out with a thin rod. It didn't work. This forge is too cold to weld (under 2200 F). There must be a spider in the burner or something. The burner was rusted together, so it was impossible to get a wire in to clean out the MIG tip. After banging and wrenching on it a while, I noticed that the MIG tip was pointing out of line. How could it bend like that? It wasn't being hammered all that hard . I sat down and thought about it for a while, and realized that there was no way I could lever against it to bend the strap holding it in, so it must be falling off from corrosion. Sure enough, when I poked it with a stick, it bent over.

There was no gas leaking from the connections, and the gas leaking from around the MIG tip was being sucked in by the venturi vacuum. The burner was weak and rich. It had degraded so slowly that I hadn't noticed it. Kind of like the frog in hot water story. This was caused by a faulty bodged together connection in order to make up for the inability to source a schedule 80 pipe nipple.

After it was fixed, it was much hotter. So, I decided to try (Stuart's?) trick for fixing cracked impact tool heads. I had a goofed up garage sale chisel that was cracked too deeply to grind out. Or, it would have taken too long to grind out. Bam, instant welding heat and that nice bubbling borax look. It welded up just great and worked fine, even when trying to abuse it. Great trick!!!

These things are fiddly. Gotta watch them.

[KenH]

melting copper wire is a neat trick to take temperature of forge. If it melts quickly (once forge is up to heat) then the temp is over 2,000 F.... I'll try that next heat up.

Ken H>