Piston Problems

bamaboy2006 · Mon Feb 16, 2009 10:11 am

Hello,

I have made my first 2" piston gun and I have to say this thing is a beast. Extremely load and powerful.

After about the first 3-4 shots I noticed that air was leaking out around the rubber seal on the piston and coming out the barrel. The gun will still fire but you have to be quick to keep if from loosing to much pressure.

I think that my rubber seal is too thin but I may be wrong that is why I am asking for any suggestions on what too do to stop it from leaking. My piston is made from 4 pcs of 3/4" plywood.

Any suggestions would be greatly appreciated.

Thanks

john bunsenburner · Mon Feb 16, 2009 10:26 am

Well maybe it would help us if you said it ou had an inline piston(co ax) or not, there is a great difference...If you dont know what i am talkign about check the wiki or "piston valves visually explained"...

jonnyboy · Mon Feb 16, 2009 10:44 am

How flexible is your seal? If the barrel isn't at 90 degrees you may only be getting a partial seal. I really don't see how it matters if its coax or not.

john bunsenburner · Mon Feb 16, 2009 10:56 am

Well it does make a difference...FOrexample if its a coax and he has a really big chamber then it might not push the piston agains the barrel hard eanoth...all these kinds of things...

dudeman508 · Mon Feb 16, 2009 11:22 am

Well if its a barrel sealer or a coax you have to make sure the sealing face at the beginning of the barrel is completely flat.

Pilgrimman · Mon Feb 16, 2009 11:32 am

It's either that your barrel face is not flat enough, or the sealing material has like a hairline tear in it. Post some pics! I'd love to see this beast

psycix · Mon Feb 16, 2009 12:32 pm

The pipe it seals against, is it hacksaw cut by yourself or is it the factory cut side? It should be square.
And your piston should be too.

People also have had their piston leak along the bolt that holds the sealing face.

Any pics would help.

bamaboy2006 · Mon Feb 16, 2009 12:33 pm

Thanks for the replies.

I am not really sure how to post pictures.

Barrel Sealer. The Chamber is connected to the piston housing using two tees.

Gun is similar to "MrCrowley" Golf Ball Cannon

bamaboy2006 · Mon Feb 16, 2009 12:34 pm

I cut all the pipes with a Miter Saw.

bamaboy2006 · Mon Feb 16, 2009 12:39 pm

Here is quick layout of the gun that I am talking about. It is a rough draft but I think it will explain what I am talking about.

SpudsMcGee · Mon Feb 16, 2009 12:50 pm

Why are you using a sprinkler valve?

bamaboy2006 · Mon Feb 16, 2009 12:55 pm

Because the ball valves are a not as easy to use. I was also told that I would have better performance with a sprinkler valve.

If this is not correct please let me know. I am new to this hobby so any constructive criticism is welcome.

SpudsMcGee · Mon Feb 16, 2009 12:59 pm

Yes, sprinklers do give you better performance, but with piston guns all you need is a blowgun.

jmeyer1022 · Mon Feb 16, 2009 1:06 pm

SpudsMcGee wrote:Yes, sprinklers do give you better performance, but with piston guns all you need is a blowgun.

Maybe a blowgun attached to a sprinkler valve, you are losing major performance by only using just a blowgun. Unless his pilot is air tight to his chamber then he will need more than just a blowgun. :/

bamaboy2006 · Mon Feb 16, 2009 1:08 pm

Really?

A lot of the piston guns I have seen on the forum still use sprinkler valves.

I would rather use a blow gun since it would save about 15 bucks and cut down on the over all bulkiness of the gun.

If you would not mind could you please explain this a little more.

Could you just put a barb fitting where my sprinkler valve is and run a tube to a mounted blow gun?

Piston Problems

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