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Need thoughts on launcher design

Posted: Sat Apr 21, 2007 6:40 am
by )DEMON(
I want to build a launcher for my paintball gun similar to that of the scepter universal launcher. It will operate on standard paintball gun pressure ~850 psi. I want to make it out of aluminium.

I have designed a simple push valve for it that I think will work but am not sure. It is designed to have bad flow because of the high pressure. I don't want to go into buying regs and such for it to be low pressure because the gas source will be high pressure.

I am unsure of the design but it looks promising. Is there anything I am not taking into account?

The velocity should be adjusted by varying the volume of the chamber, maybe the plug for the chamber will be designed to have threads instead of being bolted in. I also think I will make a slide forward barrel for easy loading.

Posted: Sat Apr 21, 2007 6:50 am
by Hotwired
The valve system looks like it'll work... just as long as the o-rings will stay sealed at 850psi.

Is this meant to be a full auto design?

Posted: Sat Apr 21, 2007 7:00 am
by )DEMON(
Uh, no. I just realized why you asked that. The air chamber is filled once and fired once befor being filled again. So it is just single shot.

The orings should stay sealed, they seal in paintball guns at the same pressure.

Posted: Sat Apr 21, 2007 7:17 am
by lukemc
you have a ball valve that is rated over 800 psi??

Posted: Sat Apr 21, 2007 7:28 am
by thrasmussen
It has potential but I can see some flaws in the design.
The whole thing should be turned around and the bore for the ball valve should accept the barrel, and the one for the barrel should be used as a venting hole and you make it into a diaphragm or piston gun. Just an idea.

Posted: Sat Apr 21, 2007 7:35 am
by )DEMON(
Did I forget to mension that I don't want to kill people with this? An 850psi piston gun will be a little overkill. The velocity for the projectile should be around 250-270fps, that is what is allowed.

I will get a ball valve meant for paintball or high pressure hydraulics. If the valve is small enough pressure isn't a big issue. The ball valves sold for paintball use are nothing special at all. Just plain brass ball valves. Yet they work fine for high pressure.

Posted: Sat Apr 21, 2007 7:58 am
by scatdawg
it looks like a good design. theres only one way to find out. build and test. dont forget to post results

Posted: Sat Apr 21, 2007 8:32 am
by Hotwired
I suspect speed will be rather more variable than in an electro-pneumatic commerical type because of the manual opening of the valve.

If you add a lever or large button to the valve trigger to reduce the force needed to operate it then it would be more comfortable and easier to pull which could mean less variations in speed.

Posted: Sun Apr 22, 2007 1:23 am
by )DEMON(
Yes I have thought of adding a lever to the valve, it will simply be a two finger trigger. This valve is very similar to a blowgun.

Posted: Sun Apr 22, 2007 1:41 am
by wannabie
looks good, what did you mean a launcher for your paint ball gun do you want to shoot it at your opponents :P lol

Posted: Sun Apr 22, 2007 2:31 am
by mega_swordman
Probably. If he's going to mod a paintball gun, I figure it will be a gun for scenario games. Correct me if I'm wrong.

Posted: Sun Apr 22, 2007 3:41 am
by paddo
umm not sure if i have this right but i will just suggest it anyway.

that spring that holds up the 'green' push valve is going to have to be bloody strong to hold 850 psi and if it is strong enough how are you going to push it down it will be extremely hard to do i think.

but then again i mite have it wrong so i just thought id put up my suggestion just in case for you mate.

but if i have that wrong then thats all i can see so give it a go mate. good luck. :)

EDIT: forgot to spell check lol.

Posted: Mon Apr 23, 2007 3:01 pm
by )DEMON(
Probably. If he's going to mod a paintball gun, I figure it will be a gun for scenario games. Correct me if I'm wrong.
Bingo.
that spring that holds up the 'green' push valve is going to have to be bloody strong to hold 850 psi and if it is strong enough how are you going to push it down it will be extremely hard to do i think.
Ah, there's where you are wrong. There is equal force in the push valve, it isn't being force to one side, there's no way you will be able to exert 500kg of pressure with your thumb. Once the gas is flowing it will aid the opening of the valve.

Thanks for the comments guys, I have made a new design, ultra simple with one moving part only. Unfortunatly I am not sharing it. I have made a few pages of reseach and am discussing it with my freinds dad. He might be able to make it in his workshop.

It will be 40mm and use gas from the marker or stand alone. I hope he can make it. :D

Posted: Mon Apr 23, 2007 6:43 pm
by AmYisroelChai
To bad your not sharing it. I am about to post help for a way to make really cheap and simple Paintball mortars. :cry:

If you are willing to trade for the plans (once proven) I will trade you for a 16oz CO2 bottle and a non-disclosure contract? Its not much but its what I got for now. Let me know. I understand if not.

Also if you (or anyone) have any feedback on my design it will be very helpful:
See here http://www.spudfiles.com/forums/feedbac ... t7704.html

Posted: Tue Apr 24, 2007 1:27 pm
by )DEMON(
I am waiting till tomorrow when I get word from him. If he give the thumbs up I could explain it to you but I don't want anyone stealing my design. I see good potencial in it (until I design something better).

I would check your design but my internet is very slow.