help with pnematic pen gun
hello, recently i have gotten into spudding, and mini's are my faveourite, even though i have a nice big one
but right now i am trying to make a pen gun, and i want it to be small and easily carried around. so far i have an idea of using a copper tube from an old windchime as a barrel. it is 9cm long, and has a diametre of 6mm,
my chamber is 4cm of "1 Pvc Pipe. I have heard of many different valves on this site, but i think i should use either a ball valve (cheap and simple) or a Piston valve (better). could someone tell me where to get or make one of these for my cannon. thanks if you can. also i was thinking that, to make it mobile it would be useful to have a pump with it (attatched onto the side, pumping into the chamber directly). I cannot find any small pumps, but i have a lot of syringes, and was thinking that i could somehow make one into a pump? any help apreciated Thanks.
but right now i am trying to make a pen gun, and i want it to be small and easily carried around. so far i have an idea of using a copper tube from an old windchime as a barrel. it is 9cm long, and has a diametre of 6mm,
my chamber is 4cm of "1 Pvc Pipe. I have heard of many different valves on this site, but i think i should use either a ball valve (cheap and simple) or a Piston valve (better). could someone tell me where to get or make one of these for my cannon. thanks if you can. also i was thinking that, to make it mobile it would be useful to have a pump with it (attatched onto the side, pumping into the chamber directly). I cannot find any small pumps, but i have a lot of syringes, and was thinking that i could somehow make one into a pump? any help apreciated Thanks.
- jackssmirkingrevenge
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For a small calibre (and especially with such a short barrel) if you want decent power you're going to need a small, high pressure chamber.
Have a look at this one for some building advice.
I would suggest you get yourself a shock pump, they are relatively cheap, compact and will easily help you reach high pressure.
Have a look at this one for some building advice.
I would suggest you get yourself a shock pump, they are relatively cheap, compact and will easily help you reach high pressure.
- Mr.Sandman
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Im confused, you said you wanted a pen gun correct? Then why is your chamber 1 inch pvc? Thats way bigger than a pen.And a ball valve? Thi isnt making sense to me. penguns are the diameter of a pen but maybe shorter or longer.
Yeah, it's that important.
@Jsr: this doesnt need to be super high power,as its just going to be a plinker, for shootin' spitballs in glass etc. it would be nice to have a high power one, but im completely broke, and its hard making something good on a budget. also i have lookd into shock pumps, but as this only needs to got to 60 - 70 psi max, i dont think its worth the extra cash, which is why i want to make a syringe pump.
@ MrSandman: maybe its not a pengun, but i thought penguns were just small guns with pen tubes as a barrel? sorry iff i were wrong.
here is a diagram of how it works. and why is a ball valve making no sence to you? also, what valve should i use???
edit: I have now looked at your pengun Jsr, and was wondereing what its C:B ratio is? because mine will have a 1:1 ratio, and was wondering how powerful that would be at 60 - 70 psi? also, if i managed to make a mini pump (i also have some copper tube, so i could use that as well) and what sort of valve should i use for filling? or should i just have a tube from my pump leading direct into chamber. would that work???
@ MrSandman: maybe its not a pengun, but i thought penguns were just small guns with pen tubes as a barrel? sorry iff i were wrong.
here is a diagram of how it works. and why is a ball valve making no sence to you? also, what valve should i use???
edit: I have now looked at your pengun Jsr, and was wondereing what its C:B ratio is? because mine will have a 1:1 ratio, and was wondering how powerful that would be at 60 - 70 psi? also, if i managed to make a mini pump (i also have some copper tube, so i could use that as well) and what sort of valve should i use for filling? or should i just have a tube from my pump leading direct into chamber. would that work???
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- her is a diagram of how i want it too work.
- Diagram.jpg (6.35 KiB) Viewed 5462 times
- jackssmirkingrevenge
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If you use a small diameter syringe (say a 1mL or 2mL one) attached to a schrader as a check valve, you should be able to reach some pretty high pressures (keeping a small chamber) but for the low pressures you want a 10 or 20mL will be ideal as it will take a lot less strokes.EvilFish wrote:this doesnt need to be super high power,as its just going to be a plinker, for shootin' spitballs in glass etc. it would be nice to have a high power one, but im completely broke, and its hard making something good on a budget. also i have lookd into shock pumps, but as this only needs to got to 60 - 70 psi max, i dont think its worth the extra cash, which is why i want to make a syringe pump.
The term "pen gun" usually refers to a gun made to look like a pen, something like this:MrSandman: maybe its not a pengun, but i thought penguns were just small guns with pen tubes as a barrel? sorry iff i were wrong.
here is a diagram of how it works. and why is a ball valve making no sence to you? also, what valve should i use???
This is my original project that "started the trend" on spudfiles
I have now looked at your pengun Jsr, and was wondereing what its C:B ratio is? because mine will have a 1:1 ratio, and was wondering how powerful that would be at 60 - 70 psi?
I think it's around 1:1, pretty powerful but that comes from the 400 or so psi I put into it :p still, depends on the valve you use. If you're using a ball valve a higher ratio (2:1 or so) should help with power.
If you're having it permanenetly attached to the launcher, might as well fir a tube direct to the chamber, but you'll need to add some sort of check valve to stop the pressure coming back. A normal schrader is unsuitable for your purposes because it takes 70 psi just to crack it open.also, if i managed to make a mini pump (i also have some copper tube, so i could use that as well) and what sort of valve should i use for filling? or should i just have a tube from my pump leading direct into chamber. would that work???
how can i attach a syringe to a schrader valve, or make a check valve if i want to make it pump directly into the chamber? also, don't syringes suck air from the front nozzle (for sucking liquids into them) so wouldnt evrytime i pump, i'd be just taking air out of the chamber and putting it back in? would there be any way to modify it so it would fill from the back end? i was thinking that if you could show me how to make a check valve, i could simply poke some holes in the wall near the top, to let air in there. would that work?
may the FSM be with you.
may the FSM be with you.
- jackssmirkingrevenge
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That's the point of a check valve, it allows flow in only one direction so you can push air into the chamber but not suck it out. You would need a hole in the other end of the chamber body to allow the syringe to re-fill with air, or remove the plunger completely after every stroke.
It really would be much, much simpler if you coughed up a couple of dollars for a shock pump, or even a normal pressure pump, they really aren't that expensive
It really would be much, much simpler if you coughed up a couple of dollars for a shock pump, or even a normal pressure pump, they really aren't that expensive
but i wanted it to be ghetto...
however, the main point is, where can i buy ( or better yet, how can i build) a decent, small check valve?
edit: also, what sort of valve could i use as a trigger? and where would i buy/make a valvefor it (6mm diameter barrel)
however, the main point is, where can i buy ( or better yet, how can i build) a decent, small check valve?
edit: also, what sort of valve could i use as a trigger? and where would i buy/make a valvefor it (6mm diameter barrel)
- jackssmirkingrevenge
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EvilFish wrote:however, the main point is, where can I buy ( or better yet, how can I build) a decent, small check valve?
This was my interpretation
You should find small check valves at any hardware store though.
Ideally you make a piston valve, as in my pen gun. If you want to go with a ball valve it's going to be bulkier and impossible to aim, unless you make it spring loaded which is complex and still not as effective as a piston valve.what sort of valve could I use as a trigger? and where would I buy/make a valve for it (6mm diameter barrel)
but how to make a piston valve? i have looked at it, but have not found answers for building a very small piston valve. also, would I be able to build a small copper pump easily, and are there any how to's on this site? also is there a how to for the building of a check valve? i understand the whole principle, of what you have there, but it would be benifit to me if a how to was there. if i have to, i could probably figure it out myself, though.
- inonickname
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Gippetto has a guide on building a track pump. Jack has already linked you to his pengun projects which obviously involve small pistons. Gippeto's guide also involves building a check valve.
You need to do the research.
You need to do the research.
PimpAssasinG wrote:no im strong but you are a fat gay mother sucker that gets raped by black man for fun
- jackssmirkingrevenge
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As was pointed out above, doing that and using a bit of ingenuity would prove your worth to other members of the forum, no one wants to be a spoonfed babyEvilFish wrote:If I have to, I could probably figure it out myself, though.
Hehe Lol so True....
have got a basic prototype working with syringe pump, crummy leaky check valve, homemade ball valve and ridiculous amounts of duct tape...
only goes to 35 psi...
am working on making a better working version (150 - 200psi) with a mini copper pump.
Thanks for all teh help JSR, and may the FSM bless you.
Edit: aslo does anyone think that i should post a small how to on the syringe pump? it itself can pump to 80 psi. not bad for something 3 cm long and made for 35 cents...
have got a basic prototype working with syringe pump, crummy leaky check valve, homemade ball valve and ridiculous amounts of duct tape...
only goes to 35 psi...
am working on making a better working version (150 - 200psi) with a mini copper pump.
Thanks for all teh help JSR, and may the FSM bless you.
Edit: aslo does anyone think that i should post a small how to on the syringe pump? it itself can pump to 80 psi. not bad for something 3 cm long and made for 35 cents...
- inonickname
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By the way, for anyone who wonders what the hell the FSM is..
Clicky.
You could do something with the pump, but it's a concept nearly everyone here would be very familiar with.
Clicky.
You could do something with the pump, but it's a concept nearly everyone here would be very familiar with.
PimpAssasinG wrote:no im strong but you are a fat gay mother sucker that gets raped by black man for fun
inonickname is the a way u could translate the clicky link posted above about fsm , i mean wtf seriously i tryed reading that jargon and am still puzzled on as to what fsm (flying spaghetti monster ) is??
is there a chance of u dumbing it down a bit if u know what i mean.
is there a chance of u dumbing it down a bit if u know what i mean.