help with my bike valve

[joe blogs]

I am not sure where i should put my schnader valve because i am worried if it will destroy the structural integrity of the pressure vessel.
At the moment i have it on the end through the end cap. I am wondering if i could have it on the pvc joiner.

[joe blogs]

The reason i want it there is ergenomics, because i want to put an onboard pump on and shorten the pressure vessel so the cubic centimeters of volume matches the barrels volume.

btw the this gun is here http://www.spudfiles.com/forums/viewtop ... sc&start=0&

[Mr.Russ]

double post, i would say just keep it where it is.

[c19o]

I would put it where there is 2 layers of pvc. And by joiner, do you mean a coupler?

[joe blogs]

sorry about the double post. i cant keep the valve where it is because i am shortening the pressure chamber and reversing it (refer to crappy ms paint picture below). Its a pvc joiner that goes to a bush(i think thats what its called) then a copper elbow.

Bush's are the pieces that get the connectors up to the right size?

[deusXmachina]

Bushings are pieces that fit inside fittings to reduce the size of the pipe, as opposed to reducing couplings, which go on the outside. We won't get into Bushes....

And you can put the shrader valve pretty much anywhere so long as you epoxy it really well, like use your common sense don't put it right near a structural member.

[joe blogs]

structural member?

[willarddaniels]

I suggest placing the valve in the T, facing forward in front of the trigger. This way it is not poking out, it is going through double pvc and it is facing the pump.

[integral]

how much psi would u get with the onboard pump? personally i would stick with the current config or reverse the chamber and put it inside or right under the stock, since u had to nuke the stock anyway to fix the leak, alot more ergonomic and more "rifle" like. just a thought.

[joe blogs]

The pressure chamber is MUCH smaller maybe a third of the size you see there on the picture. plus i am making a different shaped stock this time so that i can reverse it. I have pictured what it would look like by comparing it to my other .22 rifle and it looks sweet. the pressure chamber is sort of like a trigger guard which you can fit your hand in.

[spudthug]

i would keep it exactly how u have it...it looks awesome and it has a good size chamber....the smaller the chamber the less power...if you are going to make the chamber smaller in length make it bigger in diameter...then it is small yet powerful...and if u really want an onboard pump put it between (or close) to the things that hold the chamber to the stock

[Slugfoot]

It occurs to me that you could (with some work and the right parts) put a pump down inside the chamber. That may be a neater solution.

[joe blogs]

If i have a barrel with much less volume, why would i keep the pressure chamber size the same. when i can shorten it and pump to the exact same PSI. When you release the valve the air keeps on coming out even when the pellet has already hit the target. What i have done is measured the cubic centimetres inside the barrel and then compared it to the pressurised pressure chamber. Then i cut it to the right size allowing a little bit more volume for the friction. If your pressure chamber size equals out the volume and the friction in the barrel why would you have this bulky, huge pressure chamber (the PSI is the force, so as long as it equals out in volume compared to the barrel the force would still be the same)

[integral]

looks like u put alot of though into it, as long as u dont lose performance with a wrong calculation, by all means shorten it. and if all goes wrong, just make a new chamber.

[mattf]

my gun looks like ur gun but im still learning on how to make air guns and im not confident about the bike valve i think its going to shoot out when i start to put air into it so wat did u do Joe??