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Posted: Fri Jun 18, 2010 8:51 pm
by spudtyrrant
yes much better

Posted: Fri Jun 18, 2010 8:57 pm
by killerbanjo
Scince you guys have been so helpfull could you please tell me weather i should use PVC or Copper, i have a small peice of 6mm aluminum tubing i could make the loading part out of and some standerd copper piping (cba to mesure it atm (involves getting out of bed))

So what do you think would be best.

Also what airsource? I was thinking of starting with a drinks bottle (600ml cus its small) at 80 PSI - would that suffice?

Posted: Fri Jun 18, 2010 9:14 pm
by ramses
I would go copper, so you can convert to un-regged CO2 later... small PVC pipe is sometimes hard to find. Copper doesn't have very many good fits in itself (cap doesn't fit snugly in the next bigger size, etc.)


For the air source, a shop compressor would be good. If you don't have one, you can usually get metal air tanks fairly cheaply ($20.00) at harbor freight. They might not have great flow, but that would be much safer, and much bigger, 5 gallons, IIRC.

Posted: Fri Jun 18, 2010 9:15 pm
by killerbanjo
Im off to bed, thanks for all the help guys.

Posted: Fri Jun 18, 2010 9:35 pm
by Lockednloaded
for your first prototype i would make it fully JSR style, look at his tutorial on epoxy casting, he uses it for may of his prototypes

Posted: Fri Jun 18, 2010 10:27 pm
by Technician1002
killerbanjo wrote:
Lockednloaded wrote:Tech's QDV tutorial video on floating o-rings.

Hmm... Please post, that could be usefull!
Find my channel on youtube. Most of the stuff is related to these forums.

Here is a start. :D http://www.youtube.com/user/Technician1002

Posted: Sat Jun 19, 2010 3:23 am
by jackssmirkingrevenge
spudtyrrant wrote:watch out jsr is going to hit you with a pile of his designs(hyper-linked of course) in order to bash you into submission and feed on your creative energy
JSR is too hungover to care, however he does see that this design is a potential farting machine, the spring and piston pressure will reach an equilibrium and *prrrrrrppppp*...

Posted: Sat Jun 19, 2010 6:57 am
by killerbanjo
Lockednloaded wrote:for your first prototype i would make it fully JSR style, look at his tutorial on epoxy casting
Anyone got a link? I can't seem to find it...


Edit:

Nvm, i found it here!

Posted: Sat Jun 19, 2010 8:39 am
by jackssmirkingrevenge
I don't think it will work with constant flow, you'll run into the same problems I had here.

Posted: Sat Jun 19, 2010 9:02 am
by jhalek90
I don't think that design will work.

You piston will only move back, if a larger surface area is exposed to air pressure than the exposed surface area of the bolt.

This design would also open very very slowly, and after it does open, the piston will just stay open.

EDIT: dam, jsr beat me to it...

What you have here sir, is a class A farting machine.

Posted: Sat Jun 19, 2010 9:25 am
by spudtyrrant
if he uses and air spring behind the piston at say..... 50 or 60 psi i think that design could work all he has to do to adjust the rate of fire is adjust the air spring and/or limit the flow.

Posted: Sat Jun 19, 2010 9:34 am
by jackssmirkingrevenge
spudtyrrant wrote:i think that design could work all he has to do to adjust the rate of fire is adjust the air spring and/or limit the flow.
Taking that road drove me to the brink of insanity, a good example - you need a "pulsing" element to make this sort of design work, hence my (obligatory linked to :roll:) following the pop-off route.

Modified pop-off valve

custom pop-off v1.0

custom pop-off v2.0

custom pop-off v3.0

Posted: Sat Jun 19, 2010 9:43 am
by spudtyrrant
well i found something that might be intriguing, i know the idea has come up of using permanent magnets before, but AFAIK there hasn't been an actual example

Posted: Sat Jun 19, 2010 6:51 pm
by killerbanjo
Well, it looks like some of you think that it will not work :(

Im now thinking about this design. Has anyone here built it before?

Posted: Sat Jun 19, 2010 7:14 pm
by clemsonguy1125
That design looks cool, are you hooking it to an air compressor though