Noob question (help me not kill myself)

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.
GrafixBoy
Private 2
Private 2
Posts: 25
Joined: Fri Sep 21, 2007 5:55 pm

Mon Sep 24, 2007 10:43 am

if Im using a modded sprinkler valve with an all metal design, how to you attach the metal pipes to the plastic sprinkler valve?
User avatar
Fnord
First Sergeant 2
First Sergeant 2
Posts: 2239
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Been thanked: 1 time
Contact:

Mon Sep 24, 2007 10:47 am

You didn't get a threaded one?
Image
GrafixBoy
Private 2
Private 2
Posts: 25
Joined: Fri Sep 21, 2007 5:55 pm

Mon Sep 24, 2007 11:10 am

i have the 1" lawn genie and it does not have threads
User avatar
Fnord
First Sergeant 2
First Sergeant 2
Posts: 2239
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Been thanked: 1 time
Contact:

Mon Sep 24, 2007 11:22 am

If the sprinkler is ment to be solvent welded to the pipe, just get a very short section of 1" pvc and a 1" threaded female adaptor and glue them on.
Then just screw the metal pipe into the adaptor and go from there.

Sprinkler valves are only rated for about 125 psi. Why all metal?
Image
GrafixBoy
Private 2
Private 2
Posts: 25
Joined: Fri Sep 21, 2007 5:55 pm

Mon Sep 24, 2007 12:17 pm

well i made a pvc cannon but i didnt use the right stuff and it blew apart. but i have tons of steel pipe fitting stuff that i can use without spending any more money. is there something you recommend using instead of the sprinkler valve?
User avatar
MaxuS
Specialist
Specialist
Posts: 198
Joined: Sun Sep 02, 2007 5:11 pm

Mon Sep 24, 2007 12:18 pm

Yeah, a QEV will do the job better.
GrafixBoy
Private 2
Private 2
Posts: 25
Joined: Fri Sep 21, 2007 5:55 pm

Mon Sep 24, 2007 12:23 pm

can you point me to somewhere that explains how a qev works?
User avatar
Fnord
First Sergeant 2
First Sergeant 2
Posts: 2239
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Been thanked: 1 time
Contact:

Mon Sep 24, 2007 12:23 pm

(edit: ok, the wiki also has an entry on QEVs: http://www.spudfiles.com/spud_wiki/index.php?title=QEV )

You have to buy QEVs online, as there are few stores that sell them. They work on the same principles as a piston valve (Look up piston valves on the wiki link at the top).

If you build a pvc cannon right, it won't blow apart. If you use pressure rated fittings, you'll be fine. Look for fittings that say nsf-pw on them somewhere.

If you have tons of steel pipe fittings, you might be able to make a metal piston valve. It's a bit advanced, so you should research for a while before attempting to build one.
Last edited by Fnord on Mon Sep 24, 2007 12:28 pm, edited 2 times in total.
Image
GrafixBoy
Private 2
Private 2
Posts: 25
Joined: Fri Sep 21, 2007 5:55 pm

Mon Sep 24, 2007 12:26 pm

i didnt use pressure rated fittings. thats why it blew apart.
GrafixBoy
Private 2
Private 2
Posts: 25
Joined: Fri Sep 21, 2007 5:55 pm

Mon Sep 24, 2007 12:32 pm

where can i buy the proper qev valve?
User avatar
Fnord
First Sergeant 2
First Sergeant 2
Posts: 2239
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Been thanked: 1 time
Contact:

Mon Sep 24, 2007 12:43 pm

Start by searching ebay for "quick exhaust valve"

Here is a lot of three QEVs for $30. (really good deal)

long link
Image
GrafixBoy
Private 2
Private 2
Posts: 25
Joined: Fri Sep 21, 2007 5:55 pm

Mon Sep 24, 2007 12:50 pm

thanks for your help man.
User avatar
MaxuS
Specialist
Specialist
Posts: 198
Joined: Sun Sep 02, 2007 5:11 pm

Mon Sep 24, 2007 1:49 pm

A QEV is basically the only valve which is easily accessable in the Uk. A 3/4" QEV will outperform a modded 1" sprinkler valve, and theres no modding required for it to work. It really depends on where in the world you live, just do a search for Quick Exhaust Valves and you should come up with some results......................You could always build a piston valve, the opening time on pistons is amazing, plus theyre cheap, need a lot of work to get it right though.
Post Reply