SpudFiles

i had an idea to build a fridge compressor assisted HPA pump,

My fridgy puts out 1000 psi...how much pressure are you shooting for???

You really think you can safely build a pump in wich you want to further compress 1000 psi??

A lot of fridge compressors won't reach anywhere near that pressure. But yeah I'm with BTB here, this would have to be built to a very high standard to be safe. (No silly stubborness with shitty carbon fibre !)

Also the flow from the fridge compressor would be too little at that pressure. You'd be much better off using a buffer cylinder regulated down to a few PSI in order to reach the max pressure faster on a small diameter pump.


Also I think you'll find the seal around the pump shaft tricky to achieve at high pressures without some proper machining tools.


You'd also want to go for a design with less dead space. A pressurised inlet does negate that effect, but still.

al-xg wrote:... this would have to be built to a very high standard to be safe. (No silly stubborness with shitty carbon fibre !)

Anyone taking odds on that happening?

Gippeto wrote:Anyone taking odds on that happening?

Just areminder from my own stable

Unless you weigh more than a Buick.....you won't be able to depress the pump handle.

velocity3x wrote:Unless you weigh more than a Buick.....you won't be able to depress the pump handle.

Maybe a hydraulic press? But that's too slow to make it worth while.

i was thinking of making it from stainless steel all custom made about 3cm wall thickness, i also had another idea for a normal pump that used a fridge compressor to push the handle down.

hey, Brian im aiming for 3000

anybody who still speaks of my carbon fiber can go rummage for it in the bin

dead space wouldn't be a problem as the diagram is just a proof of concept

possibly i could use a 3000psi grease gun in the top portion to push down the
piston

Some people use a large diameter air cylinder to push the ram in a small diameter air cylinder. The small one is typically pressurized with already high pressure (~500 psi) gas.

Here.

ramses wrote:Some people use a large diameter air cylinder to push the ram in a small diameter air cylinder. The small one is typically pressurized with already high pressure (~500 psi) gas.

Here.

i was just thinking though if 500psi was being pumped constantly through the bottom and there was an air spring of 100psi theoretically wouldn't the 500psi squish upwards until both pressures equalized then it would be easier for a person to push down the handle,

Goats spudz wrote:]i was just thinking though if 500psi was being pumped constantly through the bottom and there was an air spring of 100psi theoretically.......

Absolutely wont work! Compare the square of the piston bottom to the square area of the top of the piston.

For discussion.....If the piston was 1.5" dia and the rod was .5" dia, at 3kpsi the piston will push up with 5,301 pounds of force on the pump handle. The 100psi "Air Spring" would only counter with 156 pounds of assist. You'll still need to apply an additional 5,145 pounds of force to push the handle down.
Gain Weight!

http://www.ebay.com/itm/Benjamin-Hand-P ... auder-PCP- /270727831184?pt=LH_DefaultDomain_0&hash=item3f08a2de90

Yes I agree, even through the one I could found costs me 200 euro
You have no idea how hard it is to pump 3000psi, actually I have already tested this idea, I build a pump with about 0.8 ml dead space, 1.2cm square piston and connected it with my fridge compressor, I was able to get +- 1500 psi max, but the output flow was too low, no way to charge a paintball bottle.

wyz2285 wrote:

http://www.ebay.com/itm/Benjamin-Hand-P ... auder-PCP- /270727831184?pt=LH_DefaultDomain_0&hash=item3f08a2de90

Yes I agree, even through the one I could found costs me 200 euro
You have no idea how hard it is to pump 3000psi, actually I have already tested this idea, I build a pump with about 0.8 ml dead space, 1.2cm square piston and connected it with my fridge compressor, I was able to get +- 1500 psi max, but the output flow was too low, no way to charge a paintball bottle.

can you upload a diagram of how it was made i would like to test because i have a tiny chamber on a qev gun that could do with 1500 psi

in that case just charge it with fridge compressor or the pump, I ended up using my pump as both pump/chamber and I made a qev rifle with it , usually use it at 1000 psi, tested it to 2000 once, didn´t feel very confortable holding it with my hands .