Easiest coax piston design?

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
Procrastonator
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Wed Mar 19, 2008 9:09 am

I looked at a lot of designs and found piston valves to be very complex (i have only before built basic combustion or ball valve pneumatic guns) i thought it would be easier to just make my own piston out of hot glue. I using a piece of 1.5" pipe as a mold i made a piston to fit. i set the 1.5" pipe on the round bottom of a pop can the glue pooled in the round section creating a mushroom type end to the piston (i almost cut it off before realizing that it would be the perfect stop)

I havent done much testing yet but it seems to be pretty powerful even at fairly low psi ( i was surprised at 40 psi)

Im just wondering what you guys think about what i consider to be one of if not the easiest piston to make for beginners.

Thanks for looking
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STHORNE
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Wed Mar 19, 2008 9:12 am

I suggest you make the piston out of epoxy rather than hot glue. it will retain its shape better and is more air tight/rubbery (makes a better seal against the barrel). Otherwise, nice work. Can't wait to see results.
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jackssmirkingrevenge
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Wed Mar 19, 2008 9:27 am

I think that lip will wear/break off with repeated use at higher pressures.
hectmarr wrote:You have to make many weapons, because this field is long and short life
Procrastonator
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Wed Mar 19, 2008 9:35 am

I dont think it is going to wear off (it is actually thicker than my quick drawing) but ill keep that in mind. the glue i used is more rubbery than normal hot glue too

I also glued a piece of rubber innertube to the top to make a better seal
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Antonio
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Wed Mar 19, 2008 11:36 am

jackssmirkingrevenge wrote:I think that lip will wear/break off with repeated use at higher pressures.
What would you use as a seal? Well what I meant was the frontal seal, bc that one wears as well right, atleas to my experience?
Last edited by Antonio on Wed Mar 19, 2008 12:05 pm, edited 1 time in total.
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VH_man
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Wed Mar 19, 2008 11:42 am

i know from experience that lip is completely unnececary. its easier to just put a bumper in the back................................
Procrastonator
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Wed Mar 19, 2008 10:54 pm

not sure what you mean by frontal seal ant... the only seal it has is a circle of innertube glued to it to seal the barrel...

and vh_man the lip wasnt intentional. it just happened the way i made it and i decided not to cut it off. this way the piston only has to move like an inch and doesn't smack into anything
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jackssmirkingrevenge
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Thu Mar 20, 2008 4:10 am

Procrastonator wrote:this way the piston only has to move like an inch and doesn't smack into anything
The lip smacks the edge of the tube which the piston is travelling in, which has a small surface area and therefore exerts greater pressure on the piston structure than if you just had to have a bumper over the whole area of the base of the piston.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Thu Mar 20, 2008 4:30 am

I am pui'ng, the hot glue piiston will fail after about 3.3 shots. Btw boogaloo has been scraped.

where have you been jack? Your postcount has suffered from a major lack, you got your girl preggers didn't you..?
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When you fill your car with refined oil remember that it has been paid for with blood and guts, some from your own countrymen, most not.
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jackssmirkingrevenge
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Thu Mar 20, 2008 5:39 am

Novacastrian wrote:where have you been jack? Your postcount has suffered from a major lack, you got your girl preggers didn't you..?
I know, I've been a bad spud guru, and you're half right - got rid of her actually, discovered that her version of "commitment" was slightly dissimilar to mine so sent her packing :)

Neddless to say I've been a bit distracted of late, I prefer to go out and indulge in my vices, gathering the old posse etc. than stay home brooding in front of the PC. I'll get better, just going through a bit of a transition period at the moment.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Thu Mar 20, 2008 5:48 am

jackssmirkingrevenge wrote:
Neddless to say I've been a bit distracted of late, I prefer to go out and indulge in my vices, gathering the old posse etc. than stay home brooding in front of the PC. I'll get better, just going through a bit of a transition period at the moment.


I knew that something was cooking but seeing as though i am not a sidekick* i could not quit put my finger on it..

I applaud your stubbornness my friend, if more guys had your testicular fortitude the world would be a better place.

:wink:
America, the greatest gangster of all time. With 200 million odd foot soldiers at it's whim and call.
When you fill your car with refined oil remember that it has been paid for with blood and guts, some from your own countrymen, most not.
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jackssmirkingrevenge
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Thu Mar 20, 2008 5:55 am

I'm actually happy, and the fact that practically everyone has been congratulating me on being myself again makes me all the more convinced that this was actually a convenient happening. If I see myself drifting into whining I just look to Chopper Read and HARDEN THE F*** UP! :D

The question now is, do I spend the money I got back from the ring on a new gun, or do I "waste" it on beer, narcotics of questionable legal status and women of easy virtue? :)

sorry for the topic hijack.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Thu Mar 20, 2008 6:01 am

I say fu%k the gun, go waste it on some "women of questionable nature" and hard liquor, narcotics go a long way so be careful. :twisted: God i am bad.,.
Have fun Hombre. Give the slutsone from me!! :D
America, the greatest gangster of all time. With 200 million odd foot soldiers at it's whim and call.
When you fill your car with refined oil remember that it has been paid for with blood and guts, some from your own countrymen, most not.
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jackssmirkingrevenge
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Thu Mar 20, 2008 6:10 am

That's exactly what I'll be doing tonight, and tomorrow night :D my gun cabinet's literally full to capacity anyway.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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jackssmirkingrevenge
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Thu Mar 20, 2008 6:10 am

le douple post :roll: le mods, deletez vous s'il vous plait.
Last edited by jackssmirkingrevenge on Thu Mar 20, 2008 6:11 am, edited 1 time in total.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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