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 73 users online :: 5 registered, 0 hidden and 68 guests


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

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

The Team
Administrators
Global Moderators
global_moderators.png CS

Homemade high pressure pump

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: frankrede » Fri Aug 24, 2007 3:09 pm

I think fatigue would prevent overuse:D
dang, now I want to make my own pump.
  • 0

Current project: Afghanistan deployment
User avatar
frankrede
Lieutenant General
Lieutenant General
 
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Reputation: 0

Unread postAuthor: Hawkeye » Fri Aug 24, 2007 3:40 pm

Fatigue is not an issue with a 3/4x 24 inch pump and an appropriate chamber volume for 300 psi. it doesn't take much pumping to get that pressure.
  • 0


Hawkeye
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 462
Joined: Sun Jan 21, 2007 7:12 pm
Reputation: 0

Unread postAuthor: noname » Fri Aug 24, 2007 5:51 pm

I'd advise putting a pressure guage on the pump, unless you want to add another $12+ to the budget of every gun you make.
  • 0

User avatar
noname
Lieutenant General
Lieutenant General
 
Posts: 2699
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA
Country: United States (us)
Reputation: 9

Unread postAuthor: SpudBlaster15 » Fri Aug 24, 2007 6:45 pm

$12 for a pressure gauge?!?! I can get them for about $4, and I do plan to add one eventually.
  • 0

People should not be afraid of their governments. Governments should be afraid of their people.
User avatar
SpudBlaster15
Major General
Major General
 
Posts: 2385
Joined: Wed Oct 18, 2006 11:12 pm
Location: Canada
Country: Poland (pl)
Reputation: 3

Unread postAuthor: DYI » Fri Aug 24, 2007 7:11 pm

Where did you find a 0-400 psi gauge for $4? Cheapest I can get them is at Praxair for $15. There are the uber crappy $3 0-100 psi gauges, but they don't last too long.
  • 0

User avatar
DYI
Lieutenant General
Lieutenant General
 
Posts: 2861
Joined: Sat Jul 07, 2007 8:18 pm
Location: The People's Republic of Canuckistan
Country: Turks and Caicos Islands (tc)
Reputation: 9

Unread postAuthor: SpudBlaster15 » Fri Aug 24, 2007 7:20 pm

A store called Princess Auto (only found in Canada) sells 0-300psi pressure gauges for about $4 - $5.

I also have an "uber crappy" $3 0-100psi gauge that is accurate to 0.5psi, and has lasted nearly 9 months, and still maintains it's accuracy.
  • 0

People should not be afraid of their governments. Governments should be afraid of their people.
User avatar
SpudBlaster15
Major General
Major General
 
Posts: 2385
Joined: Wed Oct 18, 2006 11:12 pm
Location: Canada
Country: Poland (pl)
Reputation: 3

Unread postAuthor: noname » Fri Aug 24, 2007 7:27 pm

DAMN you guys are lucky! The cheapest pressure guage I can get is 1-15 psi (.1 psi increments) for $8! The next up is 0-60 psi (1 psi increments) for $12! Anything else up to 200 psi is at least $15!
  • 0

User avatar
noname
Lieutenant General
Lieutenant General
 
Posts: 2699
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA
Country: United States (us)
Reputation: 9

Sponsored

Sponsor
 


Unread postAuthor: DYI » Fri Aug 24, 2007 7:30 pm

SB15: You've been lucky with that gauge. I've had three of them die (for lack of a better phrase) on me in the past 2 months, while being used well inside their intended pressure ranges.

Noname: That must suck... I can get solid brass 0-400 psi oxygen service gauge for what it costs you to buy a normal 0-160 gauge.
  • 0

User avatar
DYI
Lieutenant General
Lieutenant General
 
Posts: 2861
Joined: Sat Jul 07, 2007 8:18 pm
Location: The People's Republic of Canuckistan
Country: Turks and Caicos Islands (tc)
Reputation: 9

Unread postAuthor: SpudBlaster15 » Fri Aug 24, 2007 8:10 pm

I have owned 2 of the $3 0-100psi gauges, and had one of them die, but it was my fault, because I accidentally left the ball valve that usually separates the meter from the chamber of my hybrid open, and after a 300+psi spike, the needle was stuck at 20psi. :lol:
  • 0

People should not be afraid of their governments. Governments should be afraid of their people.
User avatar
SpudBlaster15
Major General
Major General
 
Posts: 2385
Joined: Wed Oct 18, 2006 11:12 pm
Location: Canada
Country: Poland (pl)
Reputation: 3

Unread postAuthor: Fnord » Fri Aug 24, 2007 8:47 pm

I have also subjected a 160 psi gauge to a hybrid firing (50 times or more:). It is now stuck at 60 psi.

To everyone that has to deal with ridiculous prices for pressure gauges:
check ebay. No, really, you can find good deals on stuff like this, cause no one ever bids on them.
Long link
  • 0

Image
User avatar
Fnord
Major General
Major General
 
Posts: 2244
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Reputation: 7

Unread postAuthor: Hawkeye » Fri Aug 24, 2007 9:27 pm

I just attached a schrader temporarily to the exhaust port of my gun and attached a shock pump to that. I then pumped the gun up with the homemade pump and figured out how many strokes of the pump were needed to get the required pressure by what the shock pump gauge registered .Then you can dispense with a permanent gauge.
  • 0


Hawkeye
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 462
Joined: Sun Jan 21, 2007 7:12 pm
Reputation: 0

Unread postAuthor: SpudBlaster15 » Sat Aug 25, 2007 12:52 am

SpudBlaster15 wrote: The only part that I am worried about is the hose to pump connection, which replies on 2 hose clamps to hold the hose in place. It may leak, or possibly even come apart, but only time will tell.


Well, I have to quote myself, on account of my suspicions being true. At approximately 270psi, the hose slipped past the hose clamp holding it in place and popped out of the pump body with a loud bang. I need to figure out a better hose attachment method.

Here are some pictures of the pump internals for everyone who is wondering how it works. The design of this pump is based almost entirely on the bike pump that it replaces, scaled down to have roughly 1/2 of the cross sectional area.

The whole pump.

Image

The pump head.

Image

The bottom of the pump head.

Image

The check valve's spring, piston, and rubber sealing face.

Image

The top of the check valve's piston.

Image

The check valve's spring and piston inside the T fitting.

Image

The check valve's piston seat, a washer epoxied into the bottom of the brass fitting's socket.

Image

If anyone has any suggestion as to how to mount the hose to the pump body more effectively, please let me know. (And no, I don't want to thread the pump directly to each gun that I want to use it on)
  • 0

People should not be afraid of their governments. Governments should be afraid of their people.
User avatar
SpudBlaster15
Major General
Major General
 
Posts: 2385
Joined: Wed Oct 18, 2006 11:12 pm
Location: Canada
Country: Poland (pl)
Reputation: 3

Unread postAuthor: frankrede » Sat Aug 25, 2007 1:26 am

epoxy on hose barb? THOUSANDS OF HOSE CLAMPS!
  • 0

Current project: Afghanistan deployment
User avatar
frankrede
Lieutenant General
Lieutenant General
 
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Reputation: 0

Unread postAuthor: SpudBlaster15 » Sat Aug 25, 2007 1:29 am

I considered using epoxy, but I don't really want the assembly to be permanent.

Thousands of hose clamps might work though. :lol:
  • 0

People should not be afraid of their governments. Governments should be afraid of their people.
User avatar
SpudBlaster15
Major General
Major General
 
Posts: 2385
Joined: Wed Oct 18, 2006 11:12 pm
Location: Canada
Country: Poland (pl)
Reputation: 3

Unread postAuthor: frankrede » Sat Aug 25, 2007 3:16 am

If you could find a extended hose barb, you could add a couple more hose clamps?
  • 0

Current project: Afghanistan deployment
User avatar
frankrede
Lieutenant General
Lieutenant General
 
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Reputation: 0

PreviousNext

Return to Pneumatic Cannon Discussion

Who is online

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

Reputation System ©'