Thanks for the information.

Funny seems a post of mine got deleted or just disappeared.
I basically said that I found some of the pink teflon tape lying around and used it. Working pretty well. So now I'm leaking less than 1/4psi/sex at 80psi. Not bad.

One more quick question. How do I calculate the pressure needed to rupture burst disks? If I recall correctly, there's a constant unique to the material that is needed to calculate this. What is that constant called?

I've been using two of em. The one is about 15" and other is a little longer, maybe 18" Maybe I should secure this on a vice and use a 3 foot cheater bar? I never imagined this being such a PITA

Well I'm in no big hurry. I have a few ideas to try for tomorrow. Hopefully I get it sealed.

Main chamber is 2" galvanized. There's a black iron bushing in there before the spark model A (or T? can't remember) spark plug. On other end there's a reducer and bushings to 1/4. Outlet end has 2" aluminum cam lock threaded in.

I haven't tried the gas line teflon. I just figured how could it be ...

So basically a two part epoxy. I imagine that those fittings ain't coming off without acetylene. I have some loctite 907, so I may give that a go. Thanks

Funny I never have any problems with any of my brass fittings. I'm trying to seal the thread on various size galvanized and black iron pipe. Teflon tape just don't cut it. I even tried this "liquid teflon" stuff. I figured I'd look into permatex and see what they had. So, the "high performance ...

Many thanks to the spreadsheet that saefroch made up. Got it fired at 3x just now, but I'm having problems. Don't have small enough hose clamps for the propane hose, so I'm leaking out of those. I'm also leaking out the threads on the union and out around the burst disk.

I've been cutting out pop ...

Well I read through that and I am puzzeled. Maybe I'm just tired and need to think about it in the mourning. I took ap chem last year, but things are so idealized in class. What I took from it was that the ideal air fuel mix for propane is 4.2%, and that's it. I calculated I have approximately 6 ...

Ok, well I got that squared away. Used angle grinder and a piece of sandpaper. Everything is together including ignition. Going to have to figure out fueling. Checking out that fueling 101 thread now.

What about burst disks though? Is there a thread out there that estimates psi generated at each x ...

What's the best way to grind that lip on the one half of the union to make it flush? I'm guessing a belt sander, a few belts and a lot of time... Any other ideas?

Still have to grind the union for a flush mounting surface, setup ignition, grab a pipe wrench to tighten the big pieces a little more, and find some hose clamps for the propane hose. Oh, and I may try to setup a pull string remote ignition. Just to hit the button on the stun gun after it's armed ...

It's late so I didn't feel like fooling with it too much, so I just loosely put it together as I picked up the rest of the fittings today. I'm going to rearrange the routing from the first ball valve to air in and fuel in. Going to need to pick up a few more pieces of pipe for that. Still need to ...

Well the cap I have looks to be about 3/16" thick, but if it is bringing up question then it must be a problem spot, so I will pick up the appropriate reducers and bushing. I have to go back to the store to take back things anyways. I am going to use a T fitting in the center of the combustion ...

I was also considering running a wire though a 1/4" fitting and epoxying around it running the other wire to the chamber, the spark plug just seemed simpler. I'm not too sure if I want two offset holes in the end cap. Is tapping the spark plug into the side of the chamber really weaken it that much ...

Turns out that I do not have a 1/2" 18 tap (that is the right size for 1/4" piping right?), so I think I'm going to make a trip tonight and pick up a smaller spark plug and the tap for the end cap and spark plug. Found 2 sets of 1/2" 13 and 20, but no 18... go figure.