SpudFiles

I was thinking about a pump design the other day. Nothing revolutionary, just something that could be built by the average spudder with average tools. Something with (maybe) better efficiency than average.

Since I could not stop thinking about it, I went ahead and built it. Here it is, ready for comment.

Only power tool used: drill press

Cost to build: About 20.00 for the pump and check valve. Another 10.00 for the manifold. Gage and valve belong to my work.

Performance: 4 strokes brings the gage over 200 psi.

Thanks for looking, let me know what you think.

Edit: Added piston pic
The copper tube is 3/4" type M
Dead space approx. 0.1cu.in.
Mechanical compression ratio 103:1

Edit: Finished testing pump. Pressured to ~408psi. Held for 3 hours, then re-checked clearance at pump handle. No change. Uploading pic.

oh goody may you explain the o ring setup in it. and what size copper that is.

Please explain, and how bis is the chamber you're brining to 200 PSI?

Added poll.

Maniac,

On the intake (up) stroke, the o-ring is pushed against the bottom washer. Air enters at the gap above the o-ring and follows two passages (filed into the threaded rod) past the nut.

On the compression (down) stroke, air pressure pushes the o-ring against the upper washer and the cylinder wall, forming a seal.

As the air is compressed, the check valve reaches a point (cracking pressure) where it opens and lets the air into the manifold (and a spudgun maybe?). When the manifold pressure and spring pressure equal the cylinder pressure, the check valve seals, allowing another intake stroke.

Pizlo,

I hope I explained what you wanted, you were not very specific. I installed the pump on a manifold with a tee, gage, and venting valve. This was in the pictures. It's probably about 2 cu.in.?

The o-ring thing looks complex but also easy to contsruct.

and is that epoxy i see? JSR is going to be proud.

That is one sexy piston, great work mate.

VH_man wrote:and is that epoxy i see? JSR is going to be proud.

It was the first thing to catch my eye, looking VERY good

Those of you with copper launchers, please take note

If approved by the mods, is there a need for a how to on this pump and check valve

You don't need to approve, just go ahead and do it

And no, I don't think you can change the picture order without removing them and then reuploading them.

that very neat, good job on the pump

where did you get that checkvalve?

Thanks, it was a fun little project.

Nova, we need to find you a lady friend! But thanks all the same.


Pictorial on photobucket. Check valve and piston.

http://s245.photobucket.com/albums/gg76 ... k%20valve/


I'll sit down and flush out the instructions this weekend.

Comments with details anyone would like clarified might be of help.

Gippeto wrote:I'll sit down and flush out the instructions this weekend.

Good lord, we have another one! scroll down

She's a little beauty mate, really well done on this one. That reminds me, I better post my homemade pump I made a few weeks a go

Although you've gotten to 200psi, what's the psi max your after?

Well done again mate,

Mitch.

so your piston is basically a copy of the piston found in shock pumps, made of nuts and bolts, not a piece of aluminum nicely machined?

what do you think your check valve is rated for max? 200 psi? 300 psi? 400 psi?
if it can't go over 250 psi then i might as well just buy a brass 3/4" check valve from lowe's or home depot or any plumbing supply.

200 psi in 4 pumps in a closed tee doesn't really tell us much other than your pump can fill a small tee and hold 200 psi.
if i cap my fox hp pump it takes less than 5 strokes to max out at 300 psi.
i would prefer to know how many strokes it takes to fill a chamber that is 24" long of 3/4"(.785) copper or 11.616 cu. in. of volume to 200 psi. this would be more a "real world" measurement.

Er, um ok... I'll add more detail to the instructions.

This was not really so much a case of max psi. I have calculated that 300 psi will take a force of 154.5 pounds to achieve. If someone needs more pressure, they can either work harder or use a smaller diameter tube/piston.

The premise for this pump was to make something which a lot of people would have the tools to replicate. If I were to fire up the lathe, then sure I could make a pump with virtually 0 dead space, and a check valve good to whatever pressure I wanted. But there would be only a few here that could reproduce it.
I believe that the check valve will easily go past 250psi, but no, I have not calculated a max rating. Even if I were to crunch the numbers, different manufacturing techniques (silver soldering ,sweating, epoxying) would alter the properties of the material sufficiently to render the result useless.
The primary reason for building a check valve, was to reduce the amount of dead space in the pump. With your wog check valve from lowes, you have a lot of dead space (comparatively). This would require a larger swept volume to achieve a similar pressure increase.
And Finally, in an ideal world, your chamber would take 14 strokes to fill to 200psi. So in a real world, lets say less than 20.
It may not be the solution for everyone, but it should suffice for many.