SpudFiles

Hey guys.

This one I build last night had the plan for quite a while but did not have a compressor so i build a combustion the first 3 times, but the batteries and gas is always a hassle!!!

( http://www.spudfiles.com/forums/bh-2400 ... 14078.html )

I have seen the power of a pneumatic and WANTED one so i designed a simple pump and added it to my gun here she is, keep in mind she is still a work in progress. I have tested her on 85psi.

O ps the whole gun is about 1.5m long.

You had to see the fight I put up with the guy at the shop giving me class 6 pipe I said DUDE I need sch 40 or higher, no sir this is fine, maaaannnnnnn he's stubborn.

This is a very nice gun! Clean and ergonomic design. The built in pump is a nice touch. You could gain some valve performance if you modded it and used a blowgun to trigger it instead of the solenoid.

Good job overall!

bloddy nice mate

why use solenoid when you have a tee set up for a piston

very clean

Why dont you mod the valve. Only 5$ more and it increases preformance alot. Not to mention it gives you an actual trigger and makes it more realistic. Besides...Didnt you say that you didnt like the hassle of batteries? Then why are you using a solenoid?

I'm going to have to agree with everyone else: Nice job. I look forward to seeing the finished product.

Thank you guys this is still in designing form just test fired it last night my idea is a blowgun trigger but could not wait to show you!!!!!!!!!! Funny how you notice the power of Pneumatic once you build it!!!!

o ps on this moment it must look crooked to see me load because i hold the trigger hole with my finger and pump with the other hand hahah!!!

this is my first and as you can c i left a T joint on top for a piston valve I’m working on to be added later.

Edit: Put the blogun on and made the "pimped" the valve awsome!!!!!
Higher quality pics will be put on soon and the shooting will start today!!!

Posts soon

That's a real ripper of a gun there mate. I really, really like it. Job well done on incorporating a nice working pump so neatly into the design.

wow, nicely done. I built a gun by the same concept a while back. http://www.spudfiles.com/forums/pump-ac ... 258,lighte r,0.html. I was hoping id see someone else do the same. Can you describe the pump more. I assume the piston is a floating oring and is that a check valve? What psi will it go to? My only criticism is the use of pvc for the piston housing. Copper IMO will handle much better to the generated heat, and pressure, and will have a much smoother bore for the oring.

Looks great! May I ask what the pump piston is implemented out of? I always thought of using test plugs like those found for 3-4" pipe because they were bolted together with 5/16" threads, but I don't think they make smaller diameter ones that way. Probably could link one up to a pump handle with a standoff, though...

I'd also like to see the check mechanism, unless it's built into the pump piston like some designs I've seen.

Here is the side view of the pump:

Gets to 90 psi 38-40 pumps, think if the holes in the lower valve (valve 1) is smaller it would be easyer to pump.

I also have an end cap with a valve in to use the air-compressor

edit: o ps the pump is made of sch 80 pvc as smooth as a babys bottom.

That's sick. very awesome design. Mine hits 90 exactly too. With mine though, i used a commercial check valve with a ton of deadspace. So with your superior cv design, im assuming you can go to a much higher psi. If you can id make the rod come as close to end as possible.

Edit: unless that's as high as you can physically pump it.

Well made, kudos - one small comment though, given your small chamber I would have gone with a smaller diameter pump that would allow you to easily achieve higher pressures. Remember that for a given quantity of air, 160 psi in a one litre chamber will give significantly higher power than 80 psi in a 2 litre chamber.

koolaidman: thank you, yes made it to almost touch the end valve, that is why I had to put the stops in, so that I don’t hit the valve.

jackssmirkingrevenge: thank you bubby have quite trouble to get it to 100psi I was looking on Google for the answer and jehaaaa you just gave it to me thank you, going on a 3 week holiday and this will be my thing to make, shooting over into the ocean..........
Lucky me I made the pump to unscrew!!!!


Ps here is the updated pics, trigger and valves
And it’s funny how this stuff makes a huge noise, did not know this for this is my first. I LOVE IT

Just to give you an idea, I had modelled a virtual launcher on GGDT, using the same quantity of air but with ever decreasing chamber size and therefore increasing pressure, and here's what I got:

20 inch chamber at 50 psi - 406 feet per second

10 inch chamber at 100 psi - 537 feet per second

5 inch chamber at 200 psi - 684 feet per second

2.5 inch chamber at 400 psi - 830 feet per second

1.25 inch chamber at 800 psi - 958 feet per second

0.625 inch chamber at 1600 psi - 1006 feet per second

Also remember that if you make your pump half the diameter, that means you can reach 4 times the pressure with the same effort

OMG thank you man!!!!!!! thanks for your trouble!!

Ps. just to let know on this gun I removed the spring in the valve, It opens way better and faster but can it harm the valve in the long run?

So I was thinking this later on making the chamber bigger and the pump diameter smaller and longer, thank you jackssmirk