SpudFiles

How much pressure could you get in a copper chamber of say, 1 inch by 4 inches with a portable bike or ball pump, the cheap ones, like from wal mart? It doesnt seem like you could get much because it would get hard to pump.
Also, my friend is making a small pnuematic out of PVC and wants to know if you could just drill a hole in the side and glue the filling valve (from a bicycle innertube) in it. I told him it probably would just shoot out before he got good pressure, am I right?

i got to 90 psi on a standard bike pump with a 1" by 12" piece of galvanised pipe

It wouldnt make it any harder to pump with a bigger or smaller chamber, would it? all that matters is the pressure thats inside already, right?

I get 125 psi with a $10 plastic one from a bike shop,after that preasure it leaks out the hose

i used a tire valve out of a tire inner tube and it works fine you just have to leave some of thed rubber from the inner tube around the valve and then you drill your hole in the end cap or where ever and put lots of glue on the rubber that is left and all around the tire valve and then stick it through the valve and it should work fine.
hope you understand

ya, Ill let him know he should put it in the end cap, thanks

there should be a preasure rateing written on the side of the pipe, most pipes are greatly under rated, but dont push your luck to far, think safty, wear eye protection and welders apron to catch any metal fragments in case of bursting, or better yet put a piece of thick plywood between you and the cannon while chargeing, pumping up. dont count on the preasure guages being accurate, they are never rite on the money!

p.s. all opinuns given are from personal experances

p.s.s. murphys law allways applies quote- WHAT CAN GO WRONG WILL GO WRONG AT THE WRONG TIME, i think thats how it goes

Copper pipe will not burst from pressures in the range of 100 PSI. Copper is rated up to 440 PSI, and I can't even get past 150 with a bike pump, and believe me when I say that I consider myself pretty strong.

It's not going to burst.

I didnt think I could get enough for it to burst, I was just asking if it was easy to get up to pressure with a bike pump, I wouldnt go past 110 psi, but I would start slow to make sure it would hold up

Sorry, I was referring to jrrwd with my above post.

thats fine, I was kinda talking to both of ya