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 41 users online :: 3 registered, 0 hidden and 38 guests


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

Registered users: Bing [Bot], Google [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

Best kind of rubber??

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

Best kind of rubber??

Unread postAuthor: spudthug » Thu Jul 26, 2007 2:46 pm

hey guys. i was jsut wondering what the best kind of rubber was (dont be perverted...). Like material and hardness..because my sealing faces usually leak a little bit. i was going to order some off of mcmaster but first i need to know the best kind..
  • 0

4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
User avatar
spudthug
Brigadier General
Brigadier General
 
Posts: 936
Joined: Mon Feb 26, 2007 9:02 pm
Location: johnsonburg, Pa USA
Reputation: 0

Unread postAuthor: MrCrowley » Thu Jul 26, 2007 2:50 pm

Orange gasket rubber I find at hardware sotres unding the plumbing section like taps and toilets etc is usually pretty solid. It seals fine and is more then 1/8" thick.
  • 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: DYI » Thu Jul 26, 2007 2:56 pm

Butyl rubber would be very good but it's kind of expensive ($10.49 for a 12" x 12" 1/4" thick sheet). It probably would be the best choice though. I've never used it as a sealing face on piston, but I have made gaskets to seal a union with it, and it performed very well.
  • 0

User avatar
DYI
Lieutenant General
Lieutenant General
 
Posts: 2861
Joined: Sat Jul 07, 2007 8:18 pm
Location: The People's Republic of Canuckistan
Country: Turks and Caicos Islands (tc)
Reputation: 9

Unread postAuthor: spudthug » Thu Jul 26, 2007 2:56 pm

ok next time i go to ace ill look.. do you think they have it there?

edit: why would i order butyl rubber? all it is is an intertube...
  • 0

4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
User avatar
spudthug
Brigadier General
Brigadier General
 
Posts: 936
Joined: Mon Feb 26, 2007 9:02 pm
Location: johnsonburg, Pa USA
Reputation: 0

Unread postAuthor: paaiyan » Thu Jul 26, 2007 3:03 pm

Gasket rubber, like Crowley said, or if you can find some sort of silicone gasket that fits, get it. Silicone seals very well.
  • 0

"Who ever said the pen was mightier than the sword, obviously, never encountered automatic weapons."
-General Douglass MacArthur

Read my dog's blog - Life of Kilo
User avatar
paaiyan
Major General
Major General
 
Posts: 2140
Joined: Wed Dec 27, 2006 10:03 pm
Location: Central Oklahoma
Country: United States (us)
Reputation: 1

Unread postAuthor: Modderxtrordanare » Thu Jul 26, 2007 3:38 pm

Is it hard to just experiment and play around with things on your own?

Be creative, think a little.
  • 0

Spudding since '05. Proud waster of plumbing and plumbing accessories.

-Wiki
-How-To: Modding a Sprinkler Valve
User avatar
Modderxtrordanare
Donating Member
Donating Member
 
Posts: 686
Joined: Mon Nov 20, 2006 1:22 pm
Location: Texas
Reputation: 0

Unread postAuthor: dongfang » Thu Jul 26, 2007 3:53 pm

Hi

if you use o-rings as seals and the common ones are too soft, the secret formula is called: NBR 90 Shore. These o-rings are made of a harder compound (for up to 90 degrees Celsius, I have been told).
The common o-rings are called NBR 70 Shore. A softer compound. Silicone rings are even softer.

PS: In my only piston valve design so far, the sealing surface is on the valve seat (embedded o-ring) and not on the piston. After initial assembly, it did not work ... a leak of, say, 0.3 mm somewhere on the circumference. I solved it by gluing find sandpaper on the head of my spare piston and putting a shaft on it - great honing tool. It fits down the valve body tee the same as the real piston, and I got the seal surface ground to be at an exact right angle to the piston axis, even when the valve seat was not.

Is it hard to just experiment and play around with things on your own?

Be creative, think a little.


OK, but aren't seal problems the only really boring and frustrating time-wasters in pneumatic spudding? They are for me.

Regards
Soren
  • 0

User avatar
dongfang
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 448
Joined: Sun Aug 27, 2006 8:02 am
Location: Switzerland
Reputation: 0

Sponsored

Sponsor
 


Return to Pneumatic Cannon Discussion

Who is online

Registered users: Bing [Bot], Google [Bot], Yahoo [Bot]

Reputation System ©'