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aircannon questions

Posted: Sat Jun 05, 2010 12:24 pm
by nosnik
http://www.spudfiles.com/forums/goats-mcs-t12488.html
OK GUYS! first thing this gun is awesome!! (trawling for information when i can across this.) if i increase the barrel length and decrease its size by half or more will the accuracy increase? and also his using a high pressure water handle at 800psi can i use a garden hose pressure head for the same effect ( of course at a lower pressure around 40psi to 80psi) without the water handle blowing up?


also :)

Posted: Sat Jun 05, 2010 1:26 pm
by Technician1002
Patience. Check the wiki first. You may find answers to many piston questions there.

http://www.spudfiles.com/spud_wiki/inde ... ory:Valves

Right now, I see 8 registers users logged in. Many are working on combustion and other types of projects.

The problem with a garden valve is the odball fitting. It should work at the pressure it was built for.

On the first Will this work photo, not very well. When the piston is open, the piston is in the way of the flow. Look at some other piston designs where the piston retracts back past the inlet to the valve so the flow is open all the way through. They work much better.

Posted: Sat Jun 05, 2010 1:33 pm
by clemsonguy1125
Ive used garden valves in bb guns and they have been used to pilot piston valves before, some are made from cheap plastic while some are made from metal, If I were you Id use a metal one to be on the safe side but its up to you, JSR used one at 80 fine but Ive had some crack from dropping them 2 feet off the ground. Make sure you put the base of it where the pressure comes in.
BTW-a 3/4 inch threaded adapter screws into the bottom perfectly

Posted: Sat Jun 05, 2010 1:54 pm
by nosnik
lol. thanks lots guys . @ techican1002 i want to know the pressure rating cause i dont want a second explosion (happened once when i used the wrong type of pvc ) i also have no clue about qevs or pilot valves ( yes even after reading the manuals) so i am half guessing. but thanks.

@clemsong i just needed to double check cause i am an idiot. thanks :)

just another question how much do u think 1 of those small propane tanks or fire extinguisher cost?

Posted: Sat Jun 05, 2010 1:59 pm
by theBOOM
Not much about 6 or 8 dollars tops, the propane tanks have very little flow and are hard to be adapted to pneumatic purposes, the FE are a little bit easier as you can JB weld a fitting onto the exisiting extinguisher threads.

Posted: Sat Jun 05, 2010 2:03 pm
by nosnik
JB weld .... er.. (google time)'

(edit) ahhhh ok haha thanks man!

Posted: Sat Jun 05, 2010 2:13 pm
by Technician1002
A propane tank can be modified for better flow, but this is not a beginner's project.

:D Propane tank with a 2.5 inch outlet.
Image

Posted: Sat Jun 05, 2010 2:30 pm
by nosnik
my dad could probably do that. but he sold all his equipment ( the lathe and other various yet fun equipment for steelwork ) but im just looking for a smaller tank just to hold 2 or 3 shots worth of compressed air :/

Posted: Sat Jun 05, 2010 2:42 pm
by clemsonguy1125
Technically you could just use propane, you can buy cheap propane regulators, you would just have to wait a minute for the propane to expandA

Posted: Wed Jun 09, 2010 1:08 pm
by iknowmy3tables
I hope this topic isn't too old, it just didn't seem very conclusive
nosnik wrote:lol. thanks lots guys . @ techican1002 i want to know the pressure rating cause i dont want a second explosion (happened once when i used the wrong type of pvc ) i also have no clue about qevs or pilot valves ( yes even after reading the manuals) so i am half guessing. but thanks.
I don't know exactly but a garden hose valve is probably built to operate around 20-30psi, but it can handle more, if you use cheap plastic one it's more likely to break so stay below 40psi, a metal one probably won't break but just leak when the over pressurized but keep it under 80psi.
nosnik wrote:lol. thanks lots guys . @ techican1002 i want to know the pressure rating cause i dont want a second explosion (happened once when i used the wrong type of pvc ) i also have no clue about qevs or pilot valves ( yes even after reading the manuals) so i am half guessing. but thanks.

@clemsong i just needed to double check cause i am an idiot. thanks :)

just another question how much do u think 1 of those small propane tanks or fire extinguisher cost?
typically people get old used fire extinguishers or propane tanks

and just google QEV if you don't know what it is, it's simple QEVs are just valves... they are made in factories, you buy them and then you use them, you should be able to understand that

A pilot valve is a term used for a valve that opens/closes or "pilots" another valve, so the valve that triggers a piston valve is a pilot valve if you still don't understand then you just need to read more about piston valves and QEVs

btw if you just wanted to make a lower pressure smaller caliber version of what goathunter made then that's basically what this is

Posted: Wed Jun 09, 2010 1:13 pm
by nosnik
I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U I LOVE U OMG I LOVE U :DDD


thanks alot!! ive been trawling the internet for gar hose handle rates but nothing really turned up! thanks man and that link! i love u!

(edit) i was thinking of goats design with a mod on the air release. such as a burst disk so that the air can pressurise before exploding all at once. wooooooosh! hehehe. but at 30 to 40 psi.. im not sure this would work :/