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 62 users online :: 7 registered, 0 hidden and 55 guests


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

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

The Team
Administrators
Global Moderators
global_moderators.png CS

Schrader pressure limit?

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 
  • Author
    Message

Unread postAuthor: boyntonstu » Mon Sep 21, 2009 3:25 pm

Gippeto wrote:Stu, I have tried a couple of those "clip on" style chucks. They blow off at ~250psi. I use only probe style fills and threaded connections with check valves now. Trouble free.

http://www.pyramydair.com/site/articles ... d-port.jpg

Another option is these fittings used on many pcps. They have the check valve built in. For lower pressures, I'm sure you can figure how to make one from a common compressor fitting? :wink:

http://www.crosman.com/blogs/croswords/ ... shots2.jpg



The fitting I linked you to previously, does not open the valve, rather the incoming pressure must overcome the spring on the schrader. This means that when you stop pumping and go to remove the fitting, the schrader is already closed and won't leak.

The downside, is that you need to generate the extra 70psi to crack the schrader open.


Of course! Hand hitting head.

All one needs to do is to thread on a fitting onto the Schrader that seals to it. Perhaps an O ring.


I reworked my gun today with the ball valve reversed.

A Schrader pilot cannon would be very efficient and could be configured to a smooth acting trigger.

OTOH Keeping the Ball valve as a safety may be worthwhile.

I found that I had to bump the piston closed with the ball valve.

Your information gives me food for thought and I might give it a try.

Thanks for your help.

BoyntonStu
  • 0

User avatar
boyntonstu
Brigadier General
Brigadier General
 
Posts: 1039
Joined: Sun Jun 28, 2009 8:59 am
Reputation: 0

Unread postAuthor: boyntonstu » Tue Sep 22, 2009 5:28 am

jackssmirkingrevenge wrote:
Gippeto wrote:The downside, is that you need to generate the extra 70psi to crack the schrader open.


... unless you "doctor" the stem spring ;)


When the "doctor" left, how low was the temperature of the "patient" (psi)?

Did you remove a portion of the spring to weaken it?
  • 0

User avatar
boyntonstu
Brigadier General
Brigadier General
 
Posts: 1039
Joined: Sun Jun 28, 2009 8:59 am
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Tue Sep 22, 2009 5:34 am

  • 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

Previous

Return to Pneumatic Cannon Discussion

Who is online

Registered users: Baldyforks, Bing [Bot], Exabot [Bot], Google [Bot], Google Adsense [Bot], MSNbot Media, Yahoo [Bot]

Reputation System ©'