SCH40 Chamber average lifetime

A place for general potato gun questions and discussions.
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j_diz
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Mon Oct 10, 2005 8:52 pm

Fellow Spud Chuckers -

I have just completed my very first combustion launcher - thanks, in part, to this very forum!! But I have some questions I can't find the answers to in here...

Quick details: All SCH40 - 3" chamber, 24" long - 3" to 2" reducer - 2" barrel 36" long. 3" cleanout on the end of the chamber - simple BBQ ignitor with 1/2" gap between leads for perfect spark. Using Ether (starting fluid) for fuel.

Critical lessons learned - proper venting after each shot is required and if it won't fire - air it out and use even less fuel!

Question 1: What is the expected lifetime of a SCH40 chamber? How do you know when is a good time to retire a gun and build new?

Question 2: Is using Ether too much for SCH40? Could there be too much pressure? Should I use something less explosive to prevent a chamber from exploding?

Question 3: How can I guage the pressure in the chamber during a shot? I can't find any info in here.

I am just looking for some general help on these. Thanks everyone!
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CS
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Mon Oct 10, 2005 10:42 pm

1) Your cannon should outlast you as long as you keep it out of the sun to prevent sun rote.
2) No, use it all the time. Make sure your all fittings are pressure rated though. Dont know what im talking about? Use the search bar.
3) Im almost sure there been discussions in here about it just might be hard to find. Just hook a check vavle to a pressure gauge and then tap that into the side of your chamber.

If you can take a picture of your cannon and submit it so us visual people can be satisfied. For future refrence dont just use us for your answer generators (your questions today I think were good considering your a noob)
RandomSkater
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Tue Oct 11, 2005 8:33 am

There's so many different kinds of check valves, which one would be the best to use?
I'm planning getting the 0 - 100 gauge(link) from spudtech.
Would the "Brass Spring-Loaded Piston" check valve from mcmaster work ok for it?
Is it a good idea to put something like loctite on the check valve to secure it to the pressure gauge?

Sorry for adding mroe questions, but I didn't wanna make a new post when there was already a topic on the subject.
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CS
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Tue Oct 11, 2005 8:26 pm

1)Most will work all you need to do is check its pressure rating.
2)Yes its rated for 500 psi @ 180 degrees farenheit.
3)Just use teflon tape.
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j_diz
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Wed Oct 12, 2005 3:14 pm

Thanks for the replies. Seems these are abit more durable than I expected. I guess I can submit a picture, but it is really very plain and "beginner-like"....

Pimpmann22 - I don't understand your statement....For future refrence dont just use us for your answer generators (your questions today I think were good considering your a noob)

What does that mean? I thought forums were for Q&A?
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boilingleadbath
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Wed Oct 12, 2005 4:04 pm

Well, we generaly don't like newbish questions... especialy if they are asked several times per week. However, these whould be acctually hard to find:
1) Was not even discussed on this forum. Discussion was heavily dosed with tenicaly language, which people don't usualy use in searches.
2) ...not nearly as hard as the other two. Probably been discussed a few times, and many have stated that they use it. Probably would have been delivered with a quick search.
3) The combustion people don't do this; it's (almost?) exclusivly practiced by the hybrid people. Furthermore, if you didn't know what words we typicaly use to discuss things like this, you'd have to dig through the <i>entire</i> hybrid section, or even the whole site. Someone should probably type up a how-to, but someone who has acctually done it - not me, that is.
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