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 67 users online :: 5 registered, 0 hidden and 62 guests


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

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

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

high pressure pump

Unread postAuthor: spudamine » Fri May 08, 2009 6:29 pm

here's a pump I've just finished putting together, I wanted something with the speed of a track pump but the higher pressure capability of a shock pump, I've seen a few nice pumps on this site and some hints on how to take it a step further.
I didn't feel like going down the fridge pump route, it feels kind of like cheating not to mention reliance on the national grid, environmental terrorism, and just plain lazy (I can say that, I only have a small chamber to fill :lol: )
the pump:
Image

It is a two stage design which I have taken up to 600psi so far without any difficulty, I'm sure it could go higher but I'm worried about deforming the copper, and don't have the right gauge, nor any reason to, yet.
the 1st stage is a length of 22mm OD copper, on the upstroke this is compressed into a smaller 15mm OD cylinder before being further compressed on the downstroke. The idea here is to combine the ease of pumping of the 15mm cylinder with the larger volume of the 22mm cylinder:
Image

one piston is aluminium the other brass (just what i could find) both turned on my pillar drill. Both use floating o-rings which allow air flow in one direction, each in opposing directions:
Image
(NOTE: the shaft on the 22mm piston is reversed in the pump, the piston on the right is for a separate project)

the piston shafts are M6 steel rod epoxy sleeved with 3/8 aluminium tube. The base fittings are solder fittings, the top fittings are push fit for servicability. The shaft seals are a collection of o-rings and spacer rings all crimped into sections of 22mm copper with the help of a 'pipe cutter':
Image
The check valve was the only part of the build which gave me any hassle, I splashed out on a stainless steel 40bar check valve but it didn't seal properly so I replaced the plastic piston for a brass and rubber one which works ok.
Image
(original piston on top, rebuilt piston below)
To reduce the dead space in front of the check valve there is a bolt projecting from the front of the 15mm piston which fills the fitting to the base of the elbow, I could have mounted the check valve directly to the cylinder but wanted to keep both cylinders the same length.
Image
Questions welcome.
  • 0

User avatar
spudamine
Sergeant Major
Sergeant Major
 
Posts: 184
Joined: Sun Nov 23, 2008 2:47 pm
Reputation: 0

Unread postAuthor: maverik94 » Fri May 08, 2009 6:37 pm

cool, very nice pump, I wish they sold those!
  • 0

"You can't be friends with anyone if you aren't friends with yourself."
"I'd rather be hated for who I am, than loved for who I'm not." -André Gide
Give me a lever long enough, and a fulcrum on which to place it and I shall move the world.
–Archimedes
Defeat is always momentary.
–Carl Denham

Current Project: None, I'm in Spudremission.
User avatar
maverik94
Colonel
Colonel
 
Posts: 558
Joined: Wed Jan 21, 2009 4:48 pm
Reputation: 0

Unread postAuthor: jeepkahn » Fri May 08, 2009 6:48 pm

Nicely Done.... any frame of referance of # of strokes to fill x volume to pressure???


do you think making the first stage much larger would have made it nore difficult on the upstroke???
  • 0


jeepkahn
Colonel
Colonel
 
Posts: 747
Joined: Fri Jan 09, 2009 1:11 pm
Location: Triad, NC, USA
Reputation: 0

Unread postAuthor: maverik94 » Fri May 08, 2009 6:54 pm

couldnt you try attaching the pistons at the bottom, I have a foot pump like that.
  • 0

"You can't be friends with anyone if you aren't friends with yourself."
"I'd rather be hated for who I am, than loved for who I'm not." -André Gide
Give me a lever long enough, and a fulcrum on which to place it and I shall move the world.
–Archimedes
Defeat is always momentary.
–Carl Denham

Current Project: None, I'm in Spudremission.
User avatar
maverik94
Colonel
Colonel
 
Posts: 558
Joined: Wed Jan 21, 2009 4:48 pm
Reputation: 0

Unread postAuthor: inonickname » Fri May 08, 2009 7:18 pm

They do sell them. You can buy two or three stage pumps for PCP rifles and topping off HPA cylinders, but they are rather expensive.

Very good pump! I had a think after seeing this of making my pump out of a 3/4" aluminum pipe going to a 1/2" aluminum pipe (O.D's) but decided against it. I only need 300-400 psi..

Still, awesome and good way of making a 2 stage! Can actually be achieved by those without lathes.
  • 0

PimpAssasinG wrote:no im strong but you are a fat gay mother sucker that gets raped by black man for fun
User avatar
inonickname
Lieutenant General
Lieutenant General
 
Posts: 2606
Joined: Sun Dec 07, 2008 3:27 am
Reputation: 0

Unread postAuthor: far_cry » Fri May 08, 2009 7:18 pm

that is so good
lovely look and good idea to get hpa with less time
15 mm you can get 75 bar for me its 85 moar wight :D

jeepkahn wrote:do you think making the first stage much larger would have made it nore difficult on the upstroke???

just like what he says
  • 0

ImageImage
User avatar
far_cry
Donating Member
Donating Member
 
Posts: 317
Joined: Wed Aug 20, 2008 3:59 pm
Reputation: 0

Unread postAuthor: mark.f » Fri May 08, 2009 7:21 pm

Cool. At first I thought it was a pump with two cylinders, but then I realized it was a two-stage. Good job.
  • 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: Gippeto » Fri May 08, 2009 11:08 pm

Excellent work! :D :thumbright: :thumbright:

Elegantly simple two stage design.
  • 0

"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
User avatar
Gippeto
Donating Member
Donating Member
 
Posts: 2393
Joined: Sat Jan 19, 2008 10:14 am
Location: The Great White North...Canada eh!
Reputation: 11

Unread postAuthor: jook13 » Sat May 09, 2009 12:08 am

Love it! You should sell them!
  • 0

I like to play blackjack. I'm not addicted to gambling, I'm addicted to sitting in a semi-circle.
User avatar
jook13
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 434
Joined: Mon Jan 21, 2008 10:39 pm
Location: Prescott Arizona
Reputation: 0

Unread postAuthor: spudamine » Sat May 09, 2009 5:21 am

Nicely Done.... any frame of referance of # of strokes to fill x volume to pressure???


it takes 10 strokes to take the 1/4" fill hose and fittings upto 40bar
do you think making the first stage much larger would have made it nore difficult on the upstroke???

yes but its not too bad as it is, if I was malking it again I might try a slightly larger diameter for the first stage.

Very good pump! I had a think after seeing this of making my pump out of a 3/4" aluminum pipe going to a 1/2" aluminum pipe (O.D's) but decided against it. I only need 300-400 psi..


I would have liked to use ali, its readily available with a thicker wall for a bit more stiffness, but opted for copper so i could use solder fittings.

that is so good
lovely look and good idea to get hpa with less time
15 mm you can get 75 bar for me its 85 moar wight


thanks, dead space and the available compression ratio will always limit the pressure you can actually get to below what you might expect.

Cool. At first I thought it was a pump with two cylinders, but then I realized it was a two-stage. Good job.


Actually, I initially planned to make a simple two cylinder pump with a ball valve to switch out the larger cylinder at higher pressures, but then thought I would take it a stage further when I worked out how the shaft seals could be done.

Excellent work!

Elegantly simple two stage design.


Thanks, I think I got the idea for making it two stage from one of your pump threads :)

Love it! You should sell them!


haha, it took far too long for that, cutting and drilling the stainless steel base plate in particular was a real sod.
  • 0

User avatar
spudamine
Sergeant Major
Sergeant Major
 
Posts: 184
Joined: Sun Nov 23, 2008 2:47 pm
Reputation: 0

Unread postAuthor: Carlman » Sat May 09, 2009 5:26 am

wow mate very nice! I assume a HP gun from you soon then?
  • 0

Image
Aussie spudders unite!!
User avatar
Carlman
Major General
Major General
 
Posts: 1618
Joined: Sat Nov 24, 2007 1:18 am
Location: Western Australia
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Sat May 09, 2009 5:48 am

Very impressive and well put together, both in terms of function and workmanship, kudos :)

I didn't feel like going down the fridge pump route, it feels kind of like cheating not to mention reliance on the national grid, environmental terrorism


I like the idea of a standalone unit that doesn't rely on external sources other than human power to achieve its effect.
  • 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: Mitchza89 » Sat May 09, 2009 6:52 am

Brilliant mate, absolutely brilliant. I really do take my hat off to you in this one.

Can't wait to see a nice sized bore using the sort of HP that thing will create.
  • 0

Image
User avatar
Mitchza89
Brigadier General
Brigadier General
 
Posts: 1056
Joined: Tue Jan 09, 2007 12:05 am
Reputation: 0

Unread postAuthor: c11man » Sat May 09, 2009 7:43 am

very nice pump man.

would it work to attach the outlet of a 100psi compressor to the second stage inlet instead of having a first stage?

also i dont understand floating orings so if some one could help me with that it would be great!
  • 0

User avatar
c11man
Brigadier General
Brigadier General
 
Posts: 783
Joined: Fri Feb 06, 2009 4:37 pm
Location: Wisconsin, USA
Country: United States (us)
Reputation: 0

Unread postAuthor: Mitchza89 » Sat May 09, 2009 8:25 am

The floating 0-rings on the shaft float because depending on their application, the seal has to be broken and re-seal. With the larger pump, it's to pump air into the smaller on the up stoke, and then the seal to break so it can re-fill on the downstroke.

Opposite with the smaller chamber. On the the upstroke the seal has to break to allow the chamber to fill, and then seal to further compress and push the air out the check valve.

(feels like a nerd) :D
  • 0

Image
User avatar
Mitchza89
Brigadier General
Brigadier General
 
Posts: 1056
Joined: Tue Jan 09, 2007 12:05 am
Reputation: 0

Next

Return to Pneumatic Cannon Discussion

Who is online

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

Reputation System ©'