wooden piston

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

Sun Apr 22, 2007 9:22 pm

Hi, like my competetion gun was going to be, he probably needs the space where the top elbow is for something, like a bolt-action asssembly or something.
User avatar
jrrdw
Moderator
Moderator
United States of America
Posts: 6572
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Has thanked: 39 times
Been thanked: 22 times
Contact:

Donating Members

Sun Apr 22, 2007 9:39 pm

singularity wrote:it there any reason why i have never seen a wooden piston before? im thinking about making one from oak on a lathe, that way it would be easy to add o-ring groves.
Dude check out the dates on the post.

Image

Image

Image

Action
limestonerox
Private
Private
Posts: 4
Joined: Sun Jan 21, 2007 8:27 am

Mon Apr 23, 2007 2:17 pm

what keeps the pilot chamber air from escaping up the Tee into the barrel? I don't see how you could ever pressurize the air chamber.
User avatar
singularity
Corporal 5
Corporal 5
Posts: 982
Joined: Mon Jun 26, 2006 10:53 pm
Location: someplace
Contact:

Mon Apr 23, 2007 4:48 pm

okay so the diagram isn't draw exactly right there is a stopper at the firing chamber side that prevents the piston from sliding further forward and there are o-rings on both sides of the the piston. the valve is pressurized from the pilot side there is an equalization port going through the piston

as fro not using a barrel sealing valve it would create more dead space, the idea on this gun is a small efficiently chamber so i can use a set of tanks i made for a previous project. the problem is they are small tanks so i need a small chamber. this is the most compact and efficient valve to use that would fit the requirements.
be sure to check out my <a href="http://www.spudfiles.com/forums/ak-styl ... 9.html">AK Styled Vortex Gun</a> and my <a href="http://www.spudfiles.com/forums/at-4-t9627.html">AT-4 Rocket</a>

upcoming projects... finalized clip fed BBMG and ball point pen sniper
limestonerox
Private
Private
Posts: 4
Joined: Sun Jan 21, 2007 8:27 am

Mon Apr 23, 2007 6:18 pm

I am intrigued by your design components. I've yet to build one of these and often wondered how wood would perform as a piston. Apparently well! You have answered my question about the equalization hole in the piston. Just how big should this hole be if I use a 3" pvc coupler inside a 4" pipe? The diameter of a finishing nail? Am I correct in assuming these o=rings have to be machined to a tight tolerance so air won't slip up into the Tee from the pilot chamber?

I appreciate your response. Thanks
limestonerox
Private
Private
Posts: 4
Joined: Sun Jan 21, 2007 8:27 am

Mon Apr 23, 2007 6:21 pm

BTW. what is that material wrapped around the piston on each side of the o-ring?
User avatar
jrrdw
Moderator
Moderator
United States of America
Posts: 6572
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Has thanked: 39 times
Been thanked: 22 times
Contact:

Donating Members

Mon Apr 23, 2007 6:27 pm

My equilization hole is 1/8th" placed under the rubber barrel seal to come up with a instent check valve. As for the o-rings, custom fit untill it has a slight drag on the pipe. Allways start bigger and work your way to the proper size. Mine takes a little push to get it moving, but once it starts, it's realy smooth.
User avatar
jrrdw
Moderator
Moderator
United States of America
Posts: 6572
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Has thanked: 39 times
Been thanked: 22 times
Contact:

Donating Members

Mon Apr 23, 2007 6:29 pm

limestonerox wrote:BTW. what is that material wrapped around the piston on each side of the o-ring?
It's just the wood grain, it looks wierd because i used 2 different pieces of 2X4.
Post Reply