Clean out cap problems

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Woody
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Mon Jun 01, 2009 5:17 pm

In my spud gun I noticed that gas escapes fairly easily out through the threads of my clean out cap. Also, the threads on the cap get burnt.

I was wondering if there is any setup for a cap that has a gasket in it or anything I could do to stop this. I don't care much if the threads get burnt since the part is relatively cheap, but the main problem I am addressing here is the escape of gas.

One thing that I thought of that I would like to know if this would work correctly is if I could wrap teflon tape around the clean out cape and mount a ball valve on the end so I could still ventilate it. I don't want to use an end cap and a ball valve since I still want to be able to access the inside of the combustion chamber for maintenance.

Any suggestions are very welcome.
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trigun
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Mon Jun 01, 2009 5:26 pm

well what i like to do is
-buy whatever size pvc male adapter you need
- buy pvc cap same size as the adapter
- cut small section of pipe to connect cap to male adapter
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jimmy101
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Mon Jun 01, 2009 5:38 pm

Check the threads on both parts. Cleanout caps aren't exactly precision manufactured and they often have flashing in the threads. Use a razor to clean things up and the clenaout should fit much tighter without requiring any more torque.

Latke has a page on cleanout cap cleanup:
http://www.burntlatke.com/cleanout.html
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Woody
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Mon Jun 01, 2009 6:33 pm

I already fixed up the cap prior to writing this and the flush cap I have fits very snug until it is flush with the end of the female threaded adapter.

Another question I have now is what would a good way to mount a ball valve to a clean out cap or end cap?
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Mon Jun 01, 2009 9:19 pm

Well, that's really just chewing up the weakest part of your cannon anyways, but I 'spose you could drill a 2-3/8" hole through the cap, cut a length of 2" pipe, glue a coupling on one end, insert the un-coupled end through the cap from the inside, and then trim the exposed length to the socket length of your ball valve and then glue it on.

Or, you could just get a male adapter and a bushing.

EDIT: make sure to seal it in with RTV silicone before gluing it all up. Forgot to mention that step.
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psycix
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Tue Jun 02, 2009 11:35 am

You can also use teflon tape on threads to make them stop leaking. It may, however, need to be reapplied every now and then.
what would a good way to mount a ball valve to a clean out cap or end cap?
Dont use a cap. Use a threaded adapter or simply glue the ball valve.
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boom_o_matic_2.0
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Tue Jun 02, 2009 11:41 am

on mine I put vasaline on the threads of the cleanout plug. it seals pretty good and it lubes it up. also its alot easier to replace than teflon tape.
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Woody
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Tue Jun 02, 2009 1:50 pm

ok sounds good, thanks
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