SpudFiles

Well lads, I got bored yesty and looked through my box of parts and decided to use what I had to make a ulta high pressure pump. I didn't know if I was able to make the piston so I got a bolt, the O-ring from my shock pump (I'm still yet to buy a o-ring that fits dammit!) and 2 small nuts and did what BTB did, grind the nuts down untill their round and fit the inside of the pipe to make the piston.

I was stoked that it seals perfectly so next week I'm going to get 50cm of threaded stainless rod, and stick the nuts and O ring on there to make the plunger. I'm using comp fittings for this little guy so it should be nice and easy to make.

I know it's only 50cm of 1/2'' but it's all I had lying around, I'm gonna make do with what I have.....but it's close to 3 times the volume of my shocky so I'm happy .

Nice job.

Looks like progress is good. Hope we can see it working soon.

Haha we can Only hope. The good thing about using a comp fitting is I can run the pipe straight into the T, which will make making the check valve a hell of a lot more easy .

Great job mate!If your's goes well I might seriously consider making one of these for my launcher.

They aren't expensive at all to constuct. Maybe the price of an actual shock pump ($30-40). I know it's volume isn't at all big but with my bb gun's, my shocky is just a bit too small for it so this will be perfect, I'll more then likely mount it .

Nice,having it mounted on a cannon,Hmm that gives me and idea for my musket.

How does it suck more air in to be compressed when you pull the plunger back out? I don't see a check valve. Is it the space the o-ring has to move back and forth that acts as a check valve. Sorry about the n00b question.
I thought all pumps had check valves.

The only check valve will be on the bottom of the pipe inside a Tee to stop the air from rushing back out inside the pump cylinder. This pump uses an O-ring on the piston. The top rounded off nut has a groove so when the plunger is drawn back, the groove in the nut provides a break in seal against the O-ring, so your cylinder is able to re-fill as you draw back.

I hope this has helped .

Wow thats awesome you had all the parts just lying around. I always have to buy whatever parts i need

Haha I've built so many guns and disassembled em all over the years, I have enough parts to make just about anything I want

Thats awesome. I've slowly been building up my stock of supplies by just buying an extra fitting or 2 whenever i go out

Same here, Daberno123. I buy alot of random fittings but when I'm making something theres always 1 part that needs to be bought.

I have a bunch of leftover .5in-1in pipe and fittings from my first attempts at a piston valve a couple months ago.
And Mitchza the pump looks very good so far I bet you will be able to get some pretty high pressures with the i.d of the pump body so low.

I've cheated lads. I was evening up the nuts on my piston head and fooked it. I took a look at the piston out of my shocky and saw it was unscrewable so I took it off and stuck it on the end of my plunger for the homemade pump, works absolutely perfecty so I reckon for the time being I'll be sticking with it .

It would be the bottom nut that has the groove to let the air leak in.
I think hard rubber washers are a better choice for the piston head. Less wear on the cylinder. Using metal would require smoothing them very well to avoid damage.
Old style guns commonly had the pump housed in the stock and the gun was vertically pumped up and down.