Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 34 users online :: 5 registered, 0 hidden and 29 guests


Most users ever online was 218 on Wed Dec 07, 2016 6:58 pm

Registered users: Bing [Bot], Google Adsense [Bot], Majestic-12 [Bot], MSNbot Media, Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

My first Piston Valve.

Post questions and info about pneumatic (compressed gas) powered cannons here. This includes discussion about valves, pipe types, compressors, alternate gas setups, and anything else relevant.
Sponsored 

Is this a decent piston design?

Poll ended at Sat Oct 06, 2007 11:26 pm

Yes
2
67%
No, it sucks.
1
33%
 
Total votes : 3
  • Author
    Message

My first Piston Valve.

Unread postAuthor: spudgunnerwryyyyy » Mon Oct 01, 2007 11:26 pm

This is my first piston valve, it is in a 2" tee with 1.5" porting. The piston is comprised of 1.5" pipe, 2 cast epoxy segments, foam bumper, rubber sealing face and a bolt to hold it all together.

Comments and criticisms would be apprecitated.

Hoping to hear from jackssmirkingrevenge, and McCrowley because they helped a bunch.

EDIT: This piston has been replaced by this one herehttp://www.spudfiles.com/forums/viewtopic,p,129239.html#129239
check it out it has o-rings
  • 0

Attachments
10-01-07_2113.jpg
Here is the whole valve. The 2 inch pvc with be cemented to a 2" female adapter and a 2" threaded cap will go into that.
10-01-07_2112.jpg
Piston sealing with barrel.
10-01-07_2109.jpg
Piston, top is sealing face bottom is bumper.
Last edited by spudgunnerwryyyyy on Sun Oct 28, 2007 11:59 pm, edited 1 time in total.
User avatar
spudgunnerwryyyyy
1st Lieutenant
1st Lieutenant
 
Posts: 261
Joined: Thu Jul 12, 2007 10:54 pm
Reputation: 0

Unread postAuthor: MrCrowley » Mon Oct 01, 2007 11:33 pm

Looks good, did you manage to fix the problem with all the air going out the pilot?
  • 0

User avatar
MrCrowley
Moderator
Moderator
 
Posts: 10207
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Country: New Zealand (nz)
Reputation: 4

Unread postAuthor: spudgunnerwryyyyy » Mon Oct 01, 2007 11:44 pm

Thanks, well it isn't finished yet, I need a 2" female adpater and 2" threaded plug to fit over the 2" pipe sticking out. But with my breath (3psi I checked lol) blowing from the chamber side the piston slides back 3/4" so your longer piston bigger bumper idea is working great. Any comments on if the pilot space is to large or is there any other problem.
  • 0

User avatar
spudgunnerwryyyyy
1st Lieutenant
1st Lieutenant
 
Posts: 261
Joined: Thu Jul 12, 2007 10:54 pm
Reputation: 0

Unread postAuthor: MrCrowley » Tue Oct 02, 2007 10:34 am

Is there much area on the face of the piston that is not covered by the seat(barrel) when it is sealing?

If there is not enough area the air pressure may not have enough area on the piston to push it back and fire the gun.
  • 0

User avatar
MrCrowley
Moderator
Moderator
 
Posts: 10207
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Country: New Zealand (nz)
Reputation: 4

Unread postAuthor: spud yeti » Tue Oct 02, 2007 10:46 am

That looks like a pretty decent piston valve you've got. Is it serviceable? Nice work though.
  • 0

really good quote/phrase here
User avatar
spud yeti
Brigadier General
Brigadier General
 
Posts: 1030
Joined: Tue May 08, 2007 1:41 pm
Location: Cape town south africa
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Tue Oct 02, 2007 10:47 am

looks like it should work well assuming the piston is a reasonably tight fit. 3/4" of travel is about right for that configuration, though like MrCrowley pointed out above the difference in areas between barrel and chamber isn't so great which might be a factor. Only one way to find out tho, good luck with finishing it :)
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: MrCrowley » Tue Oct 02, 2007 10:49 am

What's with the holes in the tee?

Just letting you know, while i've been here in America I decided to buy some fittings to do something similar with what you are doing with the female adapter and end cap, my old way of sticking a end cap on leaks a bit and I hate using JB Weld because it looks like sh|t on guns.
  • 0

User avatar
MrCrowley
Moderator
Moderator
 
Posts: 10207
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Country: New Zealand (nz)
Reputation: 4

Sponsored

Sponsor
 


Unread postAuthor: spudgunnerwryyyyy » Tue Oct 02, 2007 1:39 pm

Well I did do the screws to service but then I figured out the female adaptor is way easier. The piston's epoxy cast parts have enough surface area to open. I'm going to Adams Hardware today to get the parts to finish.

Edit: the piston fits perfectly and slides easy with lithium grease.
  • 0

User avatar
spudgunnerwryyyyy
1st Lieutenant
1st Lieutenant
 
Posts: 261
Joined: Thu Jul 12, 2007 10:54 pm
Reputation: 0

Unread postAuthor: spudgunnerwryyyyy » Fri Oct 05, 2007 11:31 pm

Ok I got it working. It breaks ping pong balls at 35psi with a 2"x24" chamber and a 1.5"x48" barrel. I will be posting it in the pneumatic section when I get my 3"x24" chamber hooked up. I had to use crazy amounts of white lithium grease to get it to work but now its just amazing.

Thanks again to McCrowley and jsr for all their help with getting this to work.
  • 0

The Doors are awesome, Led Zeppelin is amazing, and Motley Crue kicks @$$.
Go Orange Box

RAP SUCKS
User avatar
spudgunnerwryyyyy
1st Lieutenant
1st Lieutenant
 
Posts: 261
Joined: Thu Jul 12, 2007 10:54 pm
Reputation: 0

Unread postAuthor: mark.f » Sat Oct 06, 2007 7:40 am

Cool. Just one other question though, what is the sealing face made out out?

Like your avatar, by the way.
  • 0

User avatar
mark.f
Donating Member
Donating Member
 
Posts: 3464
Joined: Sat May 06, 2006 11:18 am
Country: United States (us)
Reputation: 21

Unread postAuthor: jackssmirkingrevenge » Sat Oct 06, 2007 8:48 am

Congrats for getting it to work :)

I had to use crazy amounts of white lithium grease to get it to work but now its just amazing.


Is this because the piston very tight in the chamber?
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: spudgunnerwryyyyy » Sat Oct 06, 2007 9:08 am

Yah the piston was pretty tight but now its just great. When I fill the pilot its loose enough to also fill the chamber but when I open the pilot the valve actuates its such a nice concept.
  • 0

The Doors are awesome, Led Zeppelin is amazing, and Motley Crue kicks @$$.
Go Orange Box

RAP SUCKS
User avatar
spudgunnerwryyyyy
1st Lieutenant
1st Lieutenant
 
Posts: 261
Joined: Thu Jul 12, 2007 10:54 pm
Reputation: 0

Unread postAuthor: spudgunnerwryyyyy » Tue Oct 09, 2007 10:28 pm

Ok, next part of build now accomplished. I put a modded 3/4" sprinkler valve to pilot because it has such a large pilot space. HUGE difference. Valve actuates with zero delay and now i can fire it much easier because its way easier to press a blow valve than to twist a 1/2" ball valve.
  • 0

The Doors are awesome, Led Zeppelin is amazing, and Motley Crue kicks @$$.
Go Orange Box

RAP SUCKS
User avatar
spudgunnerwryyyyy
1st Lieutenant
1st Lieutenant
 
Posts: 261
Joined: Thu Jul 12, 2007 10:54 pm
Reputation: 0

Unread postAuthor: spudgunnerwryyyyy » Mon Oct 29, 2007 12:00 am

  • 0

The Doors are awesome, Led Zeppelin is amazing, and Motley Crue kicks @$$.
Go Orange Box

RAP SUCKS
User avatar
spudgunnerwryyyyy
1st Lieutenant
1st Lieutenant
 
Posts: 261
Joined: Thu Jul 12, 2007 10:54 pm
Reputation: 0

Return to Pneumatic Cannon Discussion

Who is online

Registered users: Bing [Bot], Google Adsense [Bot], Majestic-12 [Bot], MSNbot Media, Yahoo [Bot]

Reputation System ©'