What cannon parts should I machine?

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Dave_424
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Tue Sep 15, 2009 4:49 pm

Hey guys, recieved my lathe a while ago and am not sure what I want to build from some scrap metal I have.

I have about 8 inches of 1 1/3" brass bar and don't really want to waste it on making smaller parts.

I was thinking about making a really high mix hybrid. Having about 10mm walls.

What mix roughly (I know it is very hard to guess) would be achieveable?

Dave
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Moonbogg
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Tue Sep 15, 2009 5:02 pm

Totally dependant on the alloy. Which alloy is it?

EDIT: Brass is simply not brass, just like a bolt isn't just a bolt.
Dave_424
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Tue Sep 15, 2009 5:06 pm

no idea to be honest, just use the weakest alloy and ill see if I like the mix number
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Moonbogg
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Tue Sep 15, 2009 5:22 pm

A quick stress analysis based on a common brass yield strength of 37kpsi, the safety factor on 1,000psi is 15. On 3,000psi its 5. This doesn't take into account any form of end caps you may use, its only the strength of the tube itself. Based on this quick study I would go for 15-20x. Drill a single hole in the chamber anywhere and your safety factor drops by about HALF!
Dave_424
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Tue Sep 15, 2009 5:35 pm

Okay then, Not really sure what to do then.

What do you suggest I make from this and other scrap pieces?

Dave
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psycix
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Wed Sep 16, 2009 4:56 am

If you would drill a hole in the side (at the back of the chamber), simply use a smaller inner diameter there.
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