Silicone Sealing Faces

Because potatoes only last one shot!
Post Reply
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

This is for people who have pistons that aren't completely sealing.

What would people think of molded silicone sealing faces for piston valves? I don't think its been done before, and silicone, when put pressure upon, flexes and stretches and would seal itself into any tiny inperfections in the seat of the valve, making it seal completely. I have a piston that isn't sealing 100% (leaks about 30 psi per minute), and I have a silicone sealing face in a mold as I'm typing this.
Tell me what you think.
Top
User avatar
spudthug
Corporal 5
Corporal 5
Posts: 936
Joined: Mon Feb 26, 2007 9:02 pm
Location: johnsonburg, Pa USA
Contact:
Contact spudthug

should work noname and i havent ever seen it done before...are u going to put it on an old gun or make a new one??id like to see it toigether with the peice if i get a piston valve i might have to do it.....btw check out my first pneumatic :D


EDIT: just posted it
Last edited by spudthug on Sun Mar 11, 2007 9:13 pm, edited 1 time in total.
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
Top
User avatar
Atlantis
Corporal 5
Corporal 5
Posts: 955
Joined: Sat Sep 03, 2005 10:26 pm
Location: Florida

I had a similar idea a while back though I never tested it. I actually made a piston out of silicone and a grocery bag, and a golf ball for weight and filling. I lined the inside of the pipe with a plastic bag and filled it with silicone, and stuck a golf ball in it to fill in the rest.
"There isn't a problem in the world that can't be solved by the proper application of explosives"
Top
User avatar
frankrede
Sergeant Major 2
Sergeant Major 2
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Has thanked: 1 time
Been thanked: 1 time

I tryed to make one in a 2" coupling using silicone out of a caulk tube but It never dryed completely after atleast 3 weeks/wth?lol
Current project: Afghanistan deployment
Top
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

How thick was it? The whole coupler? I'm just making discs, to bolt or glue onto the front of the piston to make it seal.
Top
User avatar
chaos
Sergeant 3
Sergeant 3
Posts: 1205
Joined: Wed Jan 17, 2007 8:31 am

i got some silicone sheets at work ill get my dad to pick them up during the week. i cant believe i didn't think of this.
Top
User avatar
frankrede
Sergeant Major 2
Sergeant Major 2
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Has thanked: 1 time
Been thanked: 1 time

noname wrote:How thick was it? The whole coupler? I'm just making discs, to bolt or glue onto the front of the piston to make it seal.
3/8"
Current project: Afghanistan deployment
Top
Matheusilla
Specialist
Specialist
Posts: 140
Joined: Tue Feb 13, 2007 7:43 pm

I wouldn't think that silicone would be strong enough to resist tearing and such.

I have an idea if someone would like to try it. Instead of a flat sealing face why not a round one? Like a rubber ball? And what if the rubber ball was connected to the piston with a short length of some heavy coil spring? I'm thinking that it would act like a diaphragm crossed with a piston.
Top
User avatar
A-98
Corporal 5
Corporal 5
Posts: 921
Joined: Thu Apr 27, 2006 7:41 pm
Location: Santa Barbara, CA

hot damn boy. that was a good idea. i think ive seen it posted before tho :?

however, im not sure what you mean by the spring part, could you explain.
There are rules, and then there are hundred dollar bills.
Top
Matheusilla
Specialist
Specialist
Posts: 140
Joined: Tue Feb 13, 2007 7:43 pm

The spring would connect the ball to the face of the piston and allow it to center itself in the end of the barrel/valve seat. If it is a big enough piston, the spring could be a coil over shock spring from a motorbike suspension, or at least something tense enough to be able to pull the ball away from the valve seat without stretching too much. The spring doesn't have to be very long, it's just to allow for some movement so that the ball seats well. It may have been done before but it is a completely fresh idea for me.
Top
User avatar
Hotwired
First Sergeant 3
First Sergeant 3
Posts: 2599
Joined: Fri Oct 13, 2006 5:51 am
Location: UK

Silicone would seal but it would also deform quite a bit under pressure in an undesireable way and with metal barrels it could get cut through.
Top
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

Well, it's in the mold, I'll test it in a day (if it's dry).
Top
User avatar
chaos
Sergeant 3
Sergeant 3
Posts: 1205
Joined: Wed Jan 17, 2007 8:31 am

well.........did it work?
Top
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

Patience is a virtue. :D
I popped it out of the mold this morning, it was 100% dry. I'll test it and post results when I finish my homework.
Top
User avatar
chaos
Sergeant 3
Sergeant 3
Posts: 1205
Joined: Wed Jan 17, 2007 8:31 am

$10 it will tear.........not really i don't bet money, but i think it will tear.
Top
Post Reply

Create an account or sign in to join the discussion

You need to be a member in order to post a reply

Create an account

Not a member? register to join our community
Members can start their own topics & subscribe to topics
It’s free and only takes a minute

Register

Sign in

  • Similar Topics
    Replies
    Views
    Last post

Return to “Ammo & Materials”