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 54 users online :: 4 registered, 0 hidden and 50 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

Registered users: Bing [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

First Airgun

Built a pneumatic cannon? Then post it here! This section is for completed, finished cannons that you have built. Please include pictures and information.
Sponsored 
  • Author
    Message

Unread postAuthor: Alster370 » Tue Mar 29, 2011 12:16 pm

Can i house a piston valve inside a compression tee? I was wary because it isnt the same diameter all the way though. :?
  • 0

User avatar
Alster370
2nd Lieutenant
2nd Lieutenant
 
Posts: 243
Joined: Mon Feb 21, 2011 9:34 am
Reputation: 0

Unread postAuthor: Gun Freak » Tue Mar 29, 2011 6:54 pm

Yes, it's been done before.
  • 0

OG Anti-Hybrid
One man's trash is a true Spudder's treasure!
Golf Ball Cannon "Superna"M16 BBMGPengunHammer Valve Airsoft SniperHigh Pressure .22 Coax
Holy Shat!
User avatar
Gun Freak
Lieutenant General
Lieutenant General
 
Posts: 4969
Joined: Mon Jan 25, 2010 4:38 pm
Location: Florida
Country: United States (us)
Reputation: 11

Unread postAuthor: Alster370 » Wed Mar 30, 2011 3:03 pm

Would it require any specialist tools? (lathe, pillar drill etc)

Also I have found a pump in my garage, its a SPECIALISED WINDPUMP which apparently goes to 220psi. Are pumps fitted with bleed valves? If so Could I possibly remove it so I can take the pump to 400psi? Or allow it to pump to higher pressures some other way?

Its made of steel and other strong materials so I think It could handle the extra pressure.

thanks
  • 0

User avatar
Alster370
2nd Lieutenant
2nd Lieutenant
 
Posts: 243
Joined: Mon Feb 21, 2011 9:34 am
Reputation: 0

Unread postAuthor: Gun Freak » Wed Mar 30, 2011 6:41 pm

As far as I know you can use standard compression fittings. As for the pump, if it looks strong enough to go higher then you can try, but you will have trouble pushing it at high pressure... I don't think it has any sort of bleed valve. However if you exceed the pressure on your gauge too far, the gauge may well become a bleed valve :lol:
  • 0

OG Anti-Hybrid
One man's trash is a true Spudder's treasure!
Golf Ball Cannon "Superna"M16 BBMGPengunHammer Valve Airsoft SniperHigh Pressure .22 Coax
Holy Shat!
User avatar
Gun Freak
Lieutenant General
Lieutenant General
 
Posts: 4969
Joined: Mon Jan 25, 2010 4:38 pm
Location: Florida
Country: United States (us)
Reputation: 11

Unread postAuthor: Alster370 » Sun Apr 03, 2011 4:48 am

How would I do it? Could you provide me with a link? I cant seem to find any referance of a compression fitting used to house a piston anywhere. :?

Im also stuck between two pumps, The beto 400psi shock pump (£13) or the SCOTT Shock Pump Pro 600 ( 600psi/£35). I would normally go for the higher pressure pump but I dont want the push my compression fittings too far. :?
  • 0

User avatar
Alster370
2nd Lieutenant
2nd Lieutenant
 
Posts: 243
Joined: Mon Feb 21, 2011 9:34 am
Reputation: 0

Unread postAuthor: Crna Legija » Sun Apr 03, 2011 5:45 am

this looks like a comp tee. id use something els for the barrel seal part that one is ghetto.
  • 0

'' To alcohol... The cause of, and solution to, all of life's problems.”
--Homer Simpson

Add me on ps3: wannafuk, 8/11/11 cant wait
User avatar
Crna Legija
Major General
Major General
 
Posts: 2333
Joined: Sun Jul 20, 2008 5:14 am
Location: australia
Reputation: 0

Unread postAuthor: mark.f » Sun Apr 03, 2011 9:25 am

A piston valve could be made in a compression tee, but you will either have to use very thick-walled tubing for the piston track (to bring the ID of the track equal to or smaller than the ID of the middle of the tee), or use a compression tee one size larger than your piston track.

If you are using copper, solder bushings on the outside of your piston track that bring the OD up to the ID the compression fitting is designed for.

Another way is to drill out the center of the compression fitting to increase clearance.
  • 0

User avatar
mark.f
Donating Member
Donating Member
 
Posts: 3464
Joined: Sat May 06, 2006 11:18 am
Country: United States (us)
Reputation: 21

Sponsored

Sponsor
 


Unread postAuthor: Gun Freak » Sun Apr 03, 2011 5:07 pm

The 600 psi pump has probably such a low diameter pump head it would take ages to pump up your cannon, but if you want to spend the extra money and time on it, go for it.
  • 0

OG Anti-Hybrid
One man's trash is a true Spudder's treasure!
Golf Ball Cannon "Superna"M16 BBMGPengunHammer Valve Airsoft SniperHigh Pressure .22 Coax
Holy Shat!
User avatar
Gun Freak
Lieutenant General
Lieutenant General
 
Posts: 4969
Joined: Mon Jan 25, 2010 4:38 pm
Location: Florida
Country: United States (us)
Reputation: 11

Unread postAuthor: Alster370 » Mon Apr 04, 2011 3:20 am

It would have that advantage over the beto pump that it would require less strength to reach 400psi, which would be good since it will be strapped underneath the barrel so usually I will only have one hand to pump it.

Ive also found that when a pump gets near psi limit it becomes less capable to pressurise the chamber any further. Take my floor pump for example, it will do 160psi and usually fill the chamber at about 5 psi per stroke, but when I get past 130psi it becomes more like 1 or 2 psi per stroke. :?

I wouldnt mind chatting to people who own either of these pumps to get an idea of thier performance. I know lots of people own these beto pumps or some variation of them, but I think Ive only seen one person using the scotts pump. Shame I cant remember who it was. :oops:
  • 0

User avatar
Alster370
2nd Lieutenant
2nd Lieutenant
 
Posts: 243
Joined: Mon Feb 21, 2011 9:34 am
Reputation: 0

Unread postAuthor: Alster370 » Sat Apr 16, 2011 11:55 am

Sorry for the double post but could I house a piston valve in a solder ring tee? I if so how would i go about it? I would like to redo the whole gun using solder ring fittings to reduce its bulkyness and to make it more secure but I would use high strength epoxy instead of solder.

One more thing... how do I embed pictures into a post? I would love to post a big update on the gun so far.
  • 0

User avatar
Alster370
2nd Lieutenant
2nd Lieutenant
 
Posts: 243
Joined: Mon Feb 21, 2011 9:34 am
Reputation: 0

Unread postAuthor: Labtecpower » Sat Apr 16, 2011 11:59 am

upload the pictures on imageshack or similar, and copy the forum code in the message box.
  • 0

"ñøw mÿ šįg šüçkś!"
User avatar
Labtecpower
Major General
Major General
 
Posts: 1267
Joined: Sat Feb 20, 2010 6:38 am
Location: Herb Island
Reputation: 7

Unread postAuthor: Alster370 » Mon Apr 18, 2011 3:12 am

I finally got GGDT working on my window 7 pc, so I could now see some rough performance scores. I have now realised I made a big mistake, the caliber is too small for the size of the gun. When I dialed down the figures I realised I could make a pistol with piston valve and a 1" cubed volume chamber achive just shy of 500fps with a 6mm steel ball at 400psi.

So I have decided to change the design to a pistol instead. I will prophably head down to PTS and get most of the supplies I need and hopefullly I should be done (mechanics wise) by Monday, then I can give it a good paintjob.

EDIT: I have aquired most of the parts now here is the chamber(not epoxied yet)

Image

Ive just ordered some Permatex Permapoxy which is rated at 4500PSI. :D Hopefully it should arrive thursday.
  • 0

User avatar
Alster370
2nd Lieutenant
2nd Lieutenant
 
Posts: 243
Joined: Mon Feb 21, 2011 9:34 am
Reputation: 0

Unread postAuthor: Gun Freak » Mon Apr 18, 2011 5:29 pm

Your album has a password... can't see the picture :wink:
  • 0

OG Anti-Hybrid
One man's trash is a true Spudder's treasure!
Golf Ball Cannon "Superna"M16 BBMGPengunHammer Valve Airsoft SniperHigh Pressure .22 Coax
Holy Shat!
User avatar
Gun Freak
Lieutenant General
Lieutenant General
 
Posts: 4969
Joined: Mon Jan 25, 2010 4:38 pm
Location: Florida
Country: United States (us)
Reputation: 11

Unread postAuthor: jackssmirkingrevenge » Mon Apr 18, 2011 11:50 pm

Image

Shiny :)
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: Technician1002 » Tue Apr 19, 2011 12:54 am

Naw, that's not shiney. It needs polish.

Image
  • 0

User avatar
Technician1002
Chief of Staff
Chief of Staff
 
Posts: 5190
Joined: Sat Apr 04, 2009 11:10 am
Reputation: 14

PreviousNext

Return to Pneumatic Cannon Database

Who is online

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

Reputation System ©'