First Pneumatic cannon with piston valve

[stoned]

Hi,

I've made a mini combustion gun already:



and a pneumatic with Coke PET as Chamber:



Now, two years later I'm going to make a proper pneumatic gun. I decided to use a piston valve because it seems to be the best (?).

Well, where should I start? Any tips for newcomers?
The only things that I can show you atm are some pictues of what I just rendered for the beginning:

[Mr.Sandman]

There are a few guides around here, but the most people (including me) make the piston out of whatever fits good and what we can get our hands on. I would go with this:

http://www.spudfiles.com/forums/how-to- ... 10381.html

Mr.Crowley had the idea of using a deodorant can as a piston and it seems to work well for the size gun that he does. Jsr also has this guide if you want to go small bore:
http://www.spudfiles.com/forums/making- ... t8919.html
However if you want my personal opinion, You might want to make a sprinkler valve cannon, then step up to making a piston valve cannon. If your looking for a challenge then by all means go for a piston valve. since this is your first piston valve id recommend making it inline rather than in a tee.

[stoned]

since this is your first piston valve id recommend making it inline rather than in a tee.

I only know the tee piston, how does the inline look like/work?

[Mr.Sandman]

This should answer a few of your questions: http://www.spudfiles.com/forums/piston- ... t8157.html

The tee and inline piston valves are on par in terms of performance, but inlines are more streamlined, but tees are more aesthetically pleasiing.

[tghhs]

This should answer a few of your questions: http://www.spudfiles.com/forums/piston- ... t8157.html

The tee and inline piston valves are on par in terms of performance, but inlines are more streamlined, but tees are more aesthetically pleasiing.

There not always the best looking.....
http://www.spudfiles.com/forums/tghhs-a ... 20207.html
Not to be to conceited but i reckon thats 'cleaner' than many over under launchers.

Though really the main reason so many of my cannons are Coaxial (inline) is that the housing for the piston is much more constant. The reason for this is that PVC fittings taper in. In order to gane the same constant fit for your piston, the T fitting has to be sand down so that the pipe doesn't constrict when fitted.

If this isn't done and you have made a very nice piston with a very little gap that fits perfectly in your pipe you may find that when fitted together in the T the piston will jam before it reaches the barrel.

something like this, im sure you can figure it out.