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 78 users online :: 5 registered, 1 hidden and 72 guests


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

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

The Team
Administrators
Global Moderators
global_moderators.png CS

piston help

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

piston help

Unread postAuthor: Model12 » Mon Dec 24, 2007 11:03 am

I just finished my piston cannon and now that its done I have tried it and when you pump the pilot up when you start getting to any pressure air starts whistling out of the barrel. I know the piston is against the barrel and my sealing face is the rubber from an airsoft sticky target, its really rubbery sticky stuff, also its tacky which I thought would be good. But the air keeps coming out of the barrel so has anyone else had this problem and how do you fix it?
  • 0


Model12
Private
Private
 
Posts: 23
Joined: Fri Dec 21, 2007 7:50 pm
Reputation: 0

Unread postAuthor: jrrdw » Mon Dec 24, 2007 11:08 am

Seal the bolt holding the sealing face to the piston.
  • 0

When life gives you lemons...throw them back they suck!
User avatar
jrrdw
Donating Moderator
Donating Moderator
 
Posts: 6540
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Country: United States (us)
Reputation: 25

Unread postAuthor: Model12 » Mon Dec 24, 2007 11:18 am

Never thought about that, would 5 minute Epoxy work?
  • 0


Model12
Private
Private
 
Posts: 23
Joined: Fri Dec 21, 2007 7:50 pm
Reputation: 0

Unread postAuthor: jrrdw » Mon Dec 24, 2007 12:16 pm

Model12 wrote:Never thought about that, would 5 minute Epoxy work?


Yea, just take the bolt back out and smeer a bunch in the hole and shove the bolt back in and retighten. Allow to cure fully before retrying.
  • 0

When life gives you lemons...throw them back they suck!
User avatar
jrrdw
Donating Moderator
Donating Moderator
 
Posts: 6540
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Country: United States (us)
Reputation: 25

Unread postAuthor: th3p0p0 » Mon Dec 24, 2007 1:03 pm

ok look that stuff that you are trying to use as a sealing face is not going to work. Thats why its not working. try bike tube.
  • 0

User avatar
th3p0p0
Sergeant Major
Sergeant Major
 
Posts: 194
Joined: Tue Oct 31, 2006 12:34 pm
Reputation: 0

Unread postAuthor: LikimysCrotchus5 » Mon Dec 24, 2007 1:07 pm

Not only what the others said but what are you pumping it with?

You usually want something that pums quickly and has a decent air flow.
  • 0

4SPC, My 4" piston 3" porting cannon
Memo:
Fix up copper cannon
Fix up 4SPC
Start Stirrup pump
Start Toolies piston bazooka
User avatar
LikimysCrotchus5
Brigadier General
Brigadier General
 
Posts: 1100
Joined: Tue Sep 04, 2007 10:16 pm
Reputation: 0

Unread postAuthor: Model12 » Mon Dec 24, 2007 2:43 pm

Okay first I just epoxied the sealing face, now I filled the hole with epoxy and put the bolt in and also smeared some around the washer on the front just to be sure. If this doesn't work Ill fill up every little part on the piston with epoxy. By the way I'm using a bike pump which I know is very lame but when I'm at my Dad's place I can use the brand new large compressor for my guns. But I have hope because a couple times when testing I have heard the piston slam back just a little. :lol:
  • 0


Model12
Private
Private
 
Posts: 23
Joined: Fri Dec 21, 2007 7:50 pm
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: MrCrowley » Mon Dec 24, 2007 2:47 pm

th3p0p0 wrote:ok look that stuff that you are trying to use as a sealing face is not going to work. Thats why its not working. try bike tube.


Not necessarily.

Like Jrrdw said, epoxy the bolt on the sealing face. Also make sure your seat (barrel) is perfectly flat.

If that doesn't work, try another sealing face.

Hmm bike pump could be your problem as well.
Try not to get epoxy on the actual sealing face as well.
  • 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: Model12 » Mon Dec 24, 2007 3:46 pm

YES!!! The Epoxy just dried and I tried it and it worked! It still leaks bad but I can just slap on more epoxy, but I got a Piston gun to work! This is only my third potato gun ever so thats awesome :D

Nevermind it shot kleenex but not a marble, so the piston got more epoxy :?
  • 0


Model12
Private
Private
 
Posts: 23
Joined: Fri Dec 21, 2007 7:50 pm
Reputation: 0

Unread postAuthor: MaxuS » Mon Dec 24, 2007 4:09 pm

My third gun was a copper piston spudgun, actuated by a 1/2" QEV.
What pressure have you had it up too so far?
And what is your piston made from, my one was a bolt piston..
  • 0

User avatar
MaxuS
Sergeant Major
Sergeant Major
 
Posts: 198
Joined: Sun Sep 02, 2007 5:11 pm
Reputation: 0

Unread postAuthor: Model12 » Mon Dec 24, 2007 4:41 pm

my piston is an end cap with washers and bolts and such
  • 0


Model12
Private
Private
 
Posts: 23
Joined: Fri Dec 21, 2007 7:50 pm
Reputation: 0

Unread postAuthor: psycix » Wed Dec 26, 2007 4:44 pm

I dont know up to what pressures you pump, but my piston gun leaks air UNTIL about 2 bar (30PSI)
The piston just hasnt got enough pressure on it yet to make a firm seal.
When I pump it higher it doesnt leak anymore.
  • 0

Till the day I'm dieing, I'll keep them spuddies flying, 'cause I can!

Spudfiles steam group, join!
User avatar
psycix
Donating Member
Donating Member
 
Posts: 3684
Joined: Mon Jun 25, 2007 7:12 am
Location: The Netherlands
Reputation: 0

Return to Pneumatic Cannon Discussion

Who is online

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

Reputation System ©'