First Pnuematic Cannon ~ Copper

[STHORNE]

I made this little copper beauty about 8 months ago (with the help of my dad) from some salvaged copper pipe from an old bath tub.

Im still debating whether to solder the cap with the tire valve or not because i am not sure if the rubber on the valve would shrink.... so i can only get it to about 60 psi, otherwise it leaks uncontrollably by the valve.

it shoots nails and tin foil bullets accurately up to about 50 feet, then starts to decline. marbles, about 25-30 feet because of the low psi.

so please, any suggestions to help out with the cap/tire valve are greatly appreciated....

[Lentamentalisk]

if you are scared of soldering it, just epoxy the sh!t out of it, and you should be fine. Nice look, though I would upgrade to a QEV if I were you

[potatoflinger]

That's a great design, but it does suck that you can't take it past 60 psi. Maybe you should use epoxy or a compression fitting where the fill valve is.

[invalid-username]

EEEEEEEEEPOXYYYYYYYYYYYYYYYYYYYYYYYYYYYYY

nice gun tho mayb a better valve mould be heaps better

[STHORNE]

problem is, i already tried epoxy and it works for like 3 shots, then all you hear is ppssssssshhhhhhhhh

any other ideas?

[STHORNE]

Lentamentalisk:

I would upgrade to a QEV if I were you

whats QEV?



oops, sorry bout double post

[ALIHISGREAT]

^ a quick exhaust valve, they come in two different forms, a diaphragm (usually in america) and piston (usually in europe but can be found in america) if you want some pics search for 'Quick exhaust' valve or 'qev' in the pneumatic cannon showcase.

[STHORNE]

oh, o-k. thanks... will do

thanks for the help Lentamentalisk and ALIHISGREAT.

Really appreciate it

[Sergeant Dotson]

Hey, use JB Kwik or JB Weld. Both (once hardened) are as tough as steel!
I used JB Kwik for filling a sprinkler valve. JB Kwik sets in 4 minutes, when JB Weld is basically the same thing and takes overnight. YOur choice, not mine....

[STHORNE]

but since im soldering/welding copper, it heats up very quickly and needs to be hot for the solder to stick.

but i will try your JB Kwik/Weld if it is good as you say it is.

thanks for the tip -- sthorne

[sssssbooom]

for the valve you should get a gas test gage from
http://www.plumbersurplus.com/Cat/Gas-Gauges/888/List
it looks like this

just sweat a male adapter to it and you should be good