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 80 users online :: 4 registered, 0 hidden and 76 guests


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

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

The Team
Administrators
Global Moderators
global_moderators.png CS

3 air chambers??? Is there a better way??? (UPDATED new pic)

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

Unread postAuthor: MrCrowley » Thu Apr 10, 2008 2:04 pm

With that first design with the 3 chambers, if you build it, try and buff the fittings up together so you can't see any pipe between the four way cross and the eblows :)
  • 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: ImHUGEnJAPAN » Thu Apr 10, 2008 2:14 pm

starman wrote:
ImHUGEnJAPAN wrote:What if I reduced the bore size of the barrel? lets say to 1"


Then a 1" sprinkler is closer to ideal (for a sprinkler) for a 1" barrel. If you go with a 2' barrel length and keep the tank the same, you'll have roughly 2:1 c:b ratio. A 4' barrel roughly 1:1. Depending on projectile weight, both good performers.

In your config, you still have a dead space issue on your back elbows. With your short barrel, that is contributing to your low performance as well. Move the sprinkler right behind the barrel.


Thanks for all your help guys, I thought about just starting over. I glued the threads in the sprinkler valve.....uhhhh oooops. I can't move anything unless I can break the bond of the cement and unscrew it, but I doubt it. I have some good ideas now on how to make this work better.
  • 0


ImHUGEnJAPAN
Corporal
Corporal
 
Posts: 77
Joined: Thu Apr 03, 2008 12:08 pm
Reputation: 0

Unread postAuthor: judgment_arms » Thu Apr 10, 2008 2:18 pm

Glued your fitting to the valve? Not a problem, cut off the pipe that attaches to them and glue the fittings in a piece of 1.5 inch PVC, it may take some sanding be it’ll work.
  • 0

Call me "Judge", it's easier to type.

Spud gun safety rules
User avatar
judgment_arms
Major General
Major General
 
Posts: 1272
Joined: Tue Oct 17, 2006 8:49 pm
Location: Not so beautiful North Carolina, but at least it’s the U.S.A.!
Reputation: 0

Unread postAuthor: ImHUGEnJAPAN » Thu Apr 10, 2008 2:53 pm

MrCrowley wrote:With that first design with the 3 chambers, if you build it, try and buff the fittings up together so you can't see any pipe between the four way cross and the eblows :)


That's what I am planning on doing. I hope lowes carries sch 40 2" pvc crosses and elbows, I think they do. I have extra pipe left over from the original construction.
  • 0


ImHUGEnJAPAN
Corporal
Corporal
 
Posts: 77
Joined: Thu Apr 03, 2008 12:08 pm
Reputation: 0

Unread postAuthor: ImHUGEnJAPAN » Thu Apr 10, 2008 2:57 pm

judgment_arms wrote:Glued your fitting to the valve? Not a problem, cut off the pipe that attaches to them and glue the fittings in a piece of 1.5 inch PVC, it may take some sanding be it’ll work.


I never thought of that, that might be a better option. I think I might try the bigger air chamber first. I'm Just curious to see what happens. Then I might change the design if a larger air chamber doesn't do the trick.
  • 0


ImHUGEnJAPAN
Corporal
Corporal
 
Posts: 77
Joined: Thu Apr 03, 2008 12:08 pm
Reputation: 0

Unread postAuthor: biggsauce » Thu Apr 10, 2008 3:21 pm

It wont increase your power much, sorry to say.


Well... I suppose I should consult GGDT before making statements like that :oops:
  • 0

User avatar
biggsauce
Captain
Captain
 
Posts: 338
Joined: Thu Jun 07, 2007 9:42 pm
Reputation: 0

Unread postAuthor: no-limit » Fri Apr 11, 2008 12:22 am

You say you removed the sping from inside the valve of the cp-100, I was told not to do that. Guess you can't believe everything you hear here.
  • 0

User avatar
no-limit
Sergeant
Sergeant
 
Posts: 92
Joined: Thu Apr 10, 2008 11:15 pm
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: ImHUGEnJAPAN » Fri Apr 11, 2008 10:49 am

no-limit wrote:You say you removed the sping from inside the valve of the cp-100, I was told not to do that. Guess you can't believe everything you hear here.


From what I read it seems you can do it either way. It seemed to give me a slight increase in performance. It seemed that the spring was causing the valve to close prematurely and not letting all the air out of the chamber.
  • 0


ImHUGEnJAPAN
Corporal
Corporal
 
Posts: 77
Joined: Thu Apr 03, 2008 12:08 pm
Reputation: 0

Unread postAuthor: ImHUGEnJAPAN » Sat Apr 12, 2008 8:50 am

Ok, I finally got to test fire the design this morning at 60 psi and I noticed a nice increase in power just shooting hacky sacks across my living room. I wanted to crank it all the way up, but I didn't want to put a hole in my wall. I shot one of the kids 2" superballs at about 10-20 psi pretty good. I decided that was a bad Idea inside....hahaha

If I doubled the barrel length from 20" to 40" this would probably be a pretty good cannon.

Now my Schrader valve is leaking......grrrrrr, as with life it's always something....lol. If I just screw the cap back on really fast it's ok. I will probably just replace it later.
  • 0


ImHUGEnJAPAN
Corporal
Corporal
 
Posts: 77
Joined: Thu Apr 03, 2008 12:08 pm
Reputation: 0

Unread postAuthor: jrrdw » Sat Apr 12, 2008 11:34 am

ImHUGEnJAPAN wrote:Ok, I finally got to test fire the design this morning at 60 psi and I noticed a nice increase in power just shooting hacky sacks across my living room. I wanted to crank it all the way up, but I didn't want to put a hole in my wall. I shot one of the kids 2" superballs at about 10-20 psi pretty good. I decided that was a bad Idea inside....hahaha

If I doubled the barrel length from 20" to 40" this would probably be a pretty good cannon.

Now my Schrader valve is leaking......grrrrrr, as with life it's always something....lol. If I just screw the cap back on really fast it's ok. I will probably just replace it later.


Sometimes the cores become a little loose, try screwing it a little tighter. If it spins really easy, that is probly why it leaks, unless of course it leaks where it's installed.
  • 0

When life gives you lemons...throw them back they suck!
User avatar
jrrdw
Donating Moderator
Donating Moderator
 
Posts: 6538
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Country: United States (us)
Reputation: 25

Previous

Return to Pneumatic Cannon Discussion

Who is online

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], Yahoo [Bot]

cron
Reputation System ©'