First Piston Pneumatic- Need help on Piston and such

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.
Phire
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Fri Jan 11, 2008 7:36 pm

Hey guys, its me- the lozer with the ZOMg cannon froma few months ago.. (which happened to blow up 2 inches from his head and partially scalp me) -dont hold monster cannon like bazookaz.. kthx.
anyways.
I started a piston pneumatic today- needs some help
4 inch chamber with 3/4 inner barrel- that a good ratio?
sum1 can try this out for me for sealing ideas, great value brand peanut butter jars fit in 4' barrel and leave about | | , do you think that with a few giant O rings around it it would make a good seal, i also have some high-grade silicon spray I could use on the O rings and inside of chamber together, for good lubrication, I think.

try to upload a pic tell me if design works

[img]http://h1.ripway.com/phire07/Pistonsytsme.JPG


if anyone can translate my tarible grammr plz do thx[/img]
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my 2 valve piston
my 2 valve piston
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Last edited by Phire on Fri Jan 11, 2008 7:51 pm, edited 1 time in total.
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Hotwired
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Fri Jan 11, 2008 7:42 pm

Yep, as long as the pilot is filled before the chamber it will seal and hold properly til fired.

Some might say a one way valve or a equalisation hole is less fiddly but your plan will work.
Phire
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Fri Jan 11, 2008 7:58 pm

this was kinda a prototype from stuff laying around, i didnt happen to have a 4-3/4' reducer so i got a 4 in cap and hand carved a perfect hole that i had to grease and get sum1one to help me screw the barrel into it. and after i put the glue around the inside i think it should hold real well
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DYI
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Fri Jan 11, 2008 8:21 pm

this was kinda a prototype from stuff laying around, i didnt happen to have a 4-3/4' reducer so i got a 4 in cap and hand carved a perfect hole that i had to grease and get sum1one to help me screw the barrel into it. and after i put the glue around the inside i think it should hold real well
I can see why the last gun blew up in your face... :roll:
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MrCrowley
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Fri Jan 11, 2008 8:29 pm

You live in America, so unless English is your second language, why the hell are you typing like a six year old? If English isn't your first language or you are infact six years old, I sincerely apologize.

You're going to put O-Rings on a peanut butter jar? I doubt the jar is thick enough. A sanded down 3" end cap will work, but if the gap is that big I wouldn't use it.

4" chamber, 3/4" barrel, ratio = crap.

Unless your barrel is 50' long, you're wasting a lot of air.

Use at least a 1.5" barrel for a 4" chamber.

For a 3/4" barrel, a 2" chamber will do fine. Deodorant cans fit perfectly in 2" pipe, so it would be a easy build but get very similar power to the 4" cannon.

<A HREF="http://www.spudfiles.com/forums/how-to- ... html">This is my how-to on 2" pistons.</a>
Phire
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Fri Jan 11, 2008 8:52 pm

MrCrowley wrote:You live in America, so unless English is your second language, why the hell are you typing like a six year old? If English isn't your first language or you are infact six years old, I sincerely apologize.

You're going to put O-Rings on a peanut butter jar? I doubt the jar is thick enough. A sanded down 3" end cap will work, but if the gap is that big I wouldn't use it.

4" chamber, 3/4" barrel, ratio = crap.

Unless your barrel is 50' long, you're wasting a lot of air.

Use at least a 1.5" barrel for a 4" chamber.

For a 3/4" barrel, a 2" chamber will do fine. Deodorant cans fit perfectly in 2" pipe, so it would be a easy build but get very similar power to the 4" cannon.

<A HREF="http://www.spudfiles.com/forums/how-to- ... html">This is my how-to on 2" pistons.</a>

Im 15 and hate typing normal- to much 1337 will do that to you k?
I tested out the o-rings on the jar because i thought the exact thing.
i got them off of sum oil filters about 5 minutes ago and put 4 down the length of the jar, itbent a bit on one side so I filled it with some magical great stuff and it puffed back up. Some blue grease in the chamber and its a perfect fit and moves with just a slight push. I like the 4" chamber and 3/4 barrel, makes close to 3-1 ratio which i use on alot of my things. and Ill probly invent sum special new barrel changing device for 2" 1.5 1 ect. and i promise ill sell it to you for your soul and some chips.

kthx bye

MERGED
DYI wrote:
this was kinda a prototype from stuff laying around, i didnt happen to have a 4-3/4' reducer so i got a 4 in cap and hand carved a perfect hole that i had to grease and get sum1one to help me screw the barrel into it. and after i put the glue around the inside i think it should hold real well
I can see why the last gun blew up in your face... :roll:
that may have been a mix of the 5 seconds of ether spray, my drunkeness, and a barrel with a tshirt stuffed in followed by a handfull of black walnuts. it was well made thought

MERGED

4" holds like a bazooker on the shoulder, i know i could put a 4" over a 2" or whatever, but this was just a prototype anyways. next one is a piston valve 200 gal. compressor tank with an auger pipe barrel, all attatched to a pedal driven turret and pumped by the compressors original motor on the back- i r win
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Fri Jan 11, 2008 9:26 pm

Phire wrote: Im 15 and hate typing normal- to much 1337 will do that to you k?
Oh my... :shock:

You're not going to get much help by writing posts like that. The only suggestions I can give you is learn how to safely built the gun first. If your ether powered combustion blew up then a pneumatic is even more likely to blow up unless you put some thought into safety.
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MrCrowley
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Fri Jan 11, 2008 9:32 pm

Ok I tried to help you man but if you feel like spending 20minutes to fill the chamber up with a bike pump, or use up a whole compressor tank to only reach 50psi, be my guest, but a 2" chamber will give you the same results, save you heaps of cash, be more portable and look heaps better.

Good luck with the interchangeable barrels too, it's been done before though. Not exactly that difficult, maybe for you, maybe not.

EDIT:

TO ALL MEMBERS

It seems that after clearing two pages of saboo posting and people calling him names yesterday, it seems I can no longer delete posts. They simply don't go away after I try and delete them.

And i've realised i've merged several posts into one in a few topics, unable to delete the original post, so until my deletion powers are back with me, just ignore them.

Though if you find any, PM the link so I can go back and delete them.

Thanks.
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