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leak and glue problem

Posted: Sat Jun 05, 2010 12:03 am
by fir3dp
hello!

my first post!

this is my second gun and i have bought everything. using co2!
i have a problem with my piston. its alu and i have having problem gluing rubber to the front to seal it.im using some superglue which kinna sucks. is epoxy strong enough? im using silicon anyways. any idea for anything better?

anyone here from singapore btw? haha



thanks :D

Posted: Sat Jun 05, 2010 2:03 am
by Crna Legija
epoxy dosent bond with rubber very well, use a screw

Posted: Sat Jun 05, 2010 2:03 am
by qwerty
Your best bet is drilling a hole in the alluminuim piston then screw the face onto it.

Beaten to it by like 5 seconds :roll:

Posted: Sat Jun 05, 2010 6:19 am
by jrrdw
You should use a washer and bolt set up to hold the sealing face to the piston. The washer should be all most the inside diameter of your barrel so the seal don't tear off and get blown out the barrel. Be sure and use a sealer on the bolt so air wont get past it and leak out the barrel.

Posted: Sat Jun 05, 2010 9:37 am
by fir3dp
but the diameter of the hole which the piston covers is only about 4mm. isit ok to use a whole rubber piston. like an eraser?

Posted: Sun Jun 06, 2010 2:34 am
by qwerty
Maybe but at higher pressures they often deform and stop air flow to the chamber complety.

Posted: Sun Jun 06, 2010 3:28 am
by jackssmirkingrevenge
fir3dp wrote:but the diameter of the hole which the piston covers is only about 4mm. isit ok to use a whole rubber piston. like an eraser?
I've done it several times with for example the pengun v2 and 0.22 mini.

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Posted: Sun Jun 06, 2010 7:52 am
by Crna Legija
what pressure are you planing to run it at because i don't think that a eraser would be strong enough. i used a rubber door stopper on my small colax it was quite hard and still got cut at 350 psi.

Posted: Sun Jun 06, 2010 10:42 am
by fir3dp
maybe about 200 psi? im not sure what kinna rubber i should use and cant seem to find any.. any ideas where to cut rubber from? door stopper etc?

Posted: Sun Jun 06, 2010 11:17 am
by Technician1002
In some applications it works to put the piston seal in the valve seat. This permits a lighter piston.

With proper retention, this might hold up to CO2 pressures. Insetead of an O ring, a piece of rubber hose could be secured in this fashion to make a seat that won't blow out at pressure.
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Posted: Sun Jun 06, 2010 12:22 pm
by clemsonguy1125
Try using a small rubber stopper

Posted: Sun Jun 06, 2010 2:15 pm
by kydavies
im using a cork with a piece of an old exersize ball on the end as my piston (havent tried it yet but it should work). also you can get a small piece of you pipe and grease it up then fill it up with hot glue. let it dry and hammer it out. you should have a perfect piston if you greased the pipe enough.

Posted: Sun Jun 06, 2010 6:58 pm
by Technician1002
Hot glue shrinks as it cools. It should not take too much pounding to get it out if the walls are smooth.

Posted: Tue Jun 08, 2010 11:29 am
by fir3dp
ok thanks for your replies.thinking of making a bigger barrel so i can use washers for the pistons. prob save the small one for some other time