SpudFiles

hey guys just need a quick response here, i found this on ebay.
apparently its half inch.

http://cgi.ebay.com.au/Valve-Solenoid-t ... 3:1|294:50

the gun will be all metal galvanized steel pipe etc.
how would this compare to a 3/4 inch hot glue piston valve piloted by a 1/2 ball valve?

depending on type, it may have very low flow. I'm completely unsure though.

seems relatively cheap for its size and rating but I suspect that it's flow must be considerably smaller than that of a simple 3/4" piston valve (lol I know that's a vague comment)...

so if you want to use it as the main valve you could get good optimal flow for a 10mm barrel or smaller...
for a pilot valve it's too expensive (you can find cheaper and smaller valves that will do the job - but overall solenoid diagraphm valves are no good as pilot valves - especially when compared with spool valves)


besides... I've seen better deals... for example a new 1/2" spool valve for ~10$

getting a spool valve seems like a much better idea as you can combine them with piston valves for filling/piloting... or use as the main valve... teh only problem is that most of them are rated to 10 - 15 bar

I made a homemade solenoid valve, a little different to the commercial ones.

Mine used a rod that pushes against a seal using a heavy spring, a huge surge of power using capaitors is sent through the coil and lets a short burst of air out. The commericial ones are basically just diaphragm valves just with a solenoid that releases to pocket of air beneath the diaphragm.

I tested mine up to 400psi before the pump broke, i started making one suitable for up to 800psi, but i might make a solenoid valve just like the commercial ones, there easy - plus i have about 130 sheets of 5" by 5" 1.5mm neoprene rubber to use for the diaphragms.

I might be able to sell diaphragm valves in the future rated up to 1000psi, may not be cheap as i have to cast some parts for them, inlet/oulet up to 2".

1.5mm neoprene

rated up to 1000psi

up to 2".

putting 1000 psi on a surface with 2" diameter means you better know what you're doing...

The walls need to be VERY thick, but then again..you're not going to hold a cannon like that when it fires anyway...

Well i dont make cannons anymore because they are illegal in the uk, so i stick to airsoft or other things.

I started making a valve but mesed it up so i cant really be bothered at the moment but if i make one over a 0.5" inlet/outlet then i will cast the whole thing from brass.

If i did make a cannon then its hole construction would be metal, i dont trust plastic at any pressure, if the seal was to blow then it would shoot the projectile not explode. With it being made from atleast 8mm of cast brass i think it should be pretty safe.

the only problem will be the diaphragm, it will have a steel disc behind it otherwise it would blow at about 80psi, but with the inmense pressure pushing down i think that the neoprene rubber may be too soft and get sheared.

Holding anything pressurised is risky and i would not hold the cannon, but if i were to sell the valve i know that a lot of idiots would.