making a pump?

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imjustpk
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Fri Feb 23, 2007 12:24 am

just learned about this, how can i make a pump that is durable and easy to use, up to 100-125 psi
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chaos
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Fri Feb 23, 2007 12:33 am

im interested in hearing this i hope you get some good answers

peace
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experament-u2
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Fri Feb 23, 2007 8:18 am

iv being asking this queston for a while i just gave up and when to a bike shop and forked over $60 bucks and it was the best thing iv done for my guns so far
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chaos
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Fri Feb 23, 2007 8:40 am

i may have to do the same thing if this pump i get tomorrow is crappy
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audioman81
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Fri Feb 23, 2007 9:59 am

imjustpk wrote:just learned about this, how can i make a pump that is durable and easy to use, up to 100-125 psi
dont leave us hanging, tell us more!!!
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Recruit
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Fri Feb 23, 2007 11:14 am

It is not hard to make a pump let me make a pic in paint first to demonstrate. http://s124.photobucket.com/albums/p32/ ... t=pump.jpg
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imjustpk
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Fri Feb 23, 2007 12:12 pm

well supposedly all u need is a cylinder and piston
keep_it_real
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Fri Feb 23, 2007 1:32 pm

Just use two check valves and use a rubber stopper. You can also search for high pressure pump in the pneumatic section
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chaos
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Sat Feb 24, 2007 10:26 am

keep_it_real wrote:Just use two check valves and use a rubber stopper. You can also search for high pressure pump in the pneumatic section
link us mate there a lot of posts on this site ive searched and to no prevail i have found nothing.

peace
Kenny_McCormic
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Sat Feb 24, 2007 10:42 am

http://sci-toys.com/scitoys/scitoys/aero/vacuum/ scroll down its towards the bottom
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mark.f
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Sat Feb 24, 2007 11:04 am

Alright. It would really depend on what your specific preferences are.

If you want to pump a larger volume of air at relatively low pressures, (up to around 100 PSI), you would want a cylinder with a surface area that exerts as much force as you can physically pump at 100 PSI.

If you want to pump up to really high pressures, you would want a pump with a smaller surface area, so it exerts the same force as above at, say, 250 PSI.

The pump, by itself, is relatively easy. Just get a simple double-acting cylinder, maybe 12 inches long, a tee, and two check valves. Thread the tee into the bottom port, (opposite the nose of the cylinder), and thread a check valve with the arrow going into the cylinder and a check valve with the arrow going out the cylinder. Take the check valve with the arrow going out the cylinder and then thread a female quick-disconnect for flexibilty on your output. Simple as that. Then, you just need to make a handle out of some square aluminum tubing or plastic round stock. Just thread it to the cylinder's rod thread, (some times 1/4"-28, sometimes smaller... depends), and thread it on there with some Loc-tite.
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chaos
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Sat Feb 24, 2007 11:15 am

mate thanks muchly could you just do a quick diagram im not quite sure why you need 2 check valves

peace
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mark.f
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Sat Feb 24, 2007 4:51 pm

When you pull UP on the handle, the check valve oriented into the cylinder draws air from the atmosphere into the cylinder to fill the expanding volume to atmospheric pressure. When you push DOWN on the handle, the check valve oriented towards the line pumps air into your system, while the one that draws air in seals and doesn't let air escape.

<img src="http://www.markfh11q.net/images/cylinderpump.png">
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Hotwired
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Sat Feb 24, 2007 6:15 pm

You actually only need one check valve.

If you have a look at Brian's thread here hes got a decent set of diagrams of a piston valve based on a bike pump piston head http://www.spudfiles.com/forums/viewtopic.php?t=6214&

By having that assembly on the end of the pump piston the air gets drawn in on the upstroke then forced out through the check valve under pressure on the downstroke, unable to go back up the piston tube.
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chaos
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Sat Feb 24, 2007 7:51 pm

thanks muchly guys i understand it know cheers
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