My first Combustion & Pneumatic

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.
User avatar
Punstype
Private 2
Private 2
Posts: 27
Joined: Fri Jan 26, 2007 1:04 am
Location: Hawaii

Wed Feb 07, 2007 7:39 pm

Aloha fellow Spuddies!
This is my first combustion & pneumatic spudguns, thought i would share them with the world. i started with the combustion, nothing fancy or flashy. this guy is alot of fun. i use starting fulid as a proprlent. the black piceses are abs because its hard to find pvc reducers and cupplings in Hawaii.
The pneumatic over under that i just finished (never shot) took me about a week to build. i tried to fill it with a small hand pump but could not get any pressure to build up. its to hard to do it by hand and i dont have a air compressor. dont know whats wrong? the solonoid fires and i built the batt box with parts from Radioshack. can anyone help me with the proplem i have.[/img]
Attachments
Picture from KOAS cam 186.jpg
Picture from KOAS cam 170.jpg
Picture from KOAS cam 180.jpg
Picture from KOAS cam 179.jpg
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Wed Feb 07, 2007 7:47 pm

Nice cannons, Is that ABS on the pneumatic? ABS is bad for pneumatics, but fine for combustions. Unless its the rare pressure rated stuff I wouldnt take it above 40psi.

Now for the solenoid problem. For better performance,less money and a cooler gun, get rid off the battery box and solenoid. Fill the solenoid hole with epoxy and mod the valve with a blow gun. See the how-to section for that as its stickied at the top of the page. The reason you can't build up pressure is because the valve needs about 20psi-ish to close it and stop leaking, so you need to pump bloody fast or get a air compressor.
User avatar
ballad of NJ
Private 3
Private 3
Posts: 57
Joined: Sat Feb 03, 2007 10:32 pm

Wed Feb 07, 2007 7:54 pm

nice gun but yah modify the sprinkler valve and it will do better
User avatar
frankrede
Sergeant Major 2
Sergeant Major 2
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Has thanked: 1 time
Been thanked: 1 time

Wed Feb 07, 2007 9:07 pm

Nice cannon, did you see it on PVC ballistics? Well if thats abs, you might want to replace that part with some nsf-pw.
Glad someone new here has some brains.
Well not to be racial or anything I thought spudguns were a whiteboy thing but I guess I'm wrong. Proves all men are equal, well hope you stay here in the forums and embrace the hobby
Current project: Afghanistan deployment
BIKER180360
Private 3
Private 3
Posts: 44
Joined: Tue Feb 06, 2007 12:12 pm

Wed Feb 07, 2007 9:55 pm

nice guns. the one is pretty complicated for a starter gun though. my first gun is like the second gun only mine had a grill igniter on the back of the chamber. nice job 8)
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

Wed Feb 07, 2007 10:23 pm

The first gun: Switch that ABS to pressure rated PVC NOW! ABS isn't pressure rated and is a potencial hazard.
The 2nd gun: Never glue ABS to PVC, even using the Universal Cement. Use threads if you really need to.
Other than that, they're pretty good for your first ones.
User avatar
frankrede
Sergeant Major 2
Sergeant Major 2
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Has thanked: 1 time
Been thanked: 1 time

Thu Feb 08, 2007 12:27 am

Well in a basic combustion it doesn't matter.
I have had Abs pipe glued with pvc glue that didn't blow out even at pressures above 90 psi.
Current project: Afghanistan deployment
User avatar
StealthSpud
Private 4
Private 4
Posts: 81
Joined: Thu Jan 11, 2007 9:43 pm

Thu Feb 08, 2007 2:17 pm

Yeah besides the ABs, they are some good looking guns!
User avatar
Punstype
Private 2
Private 2
Posts: 27
Joined: Fri Jan 26, 2007 1:04 am
Location: Hawaii

Fri Feb 09, 2007 6:12 am

Thanks for all the advice spuddies.
to answer some questions, that is abs on the pneumatic gun but its has SCH 40 on it, is it still safe to use? the only reason i used it is because it was affordable and if i was to buy 3" PVC here in Hawaii it cost about three times more than the ABS SCH 40.
User avatar
frankrede
Sergeant Major 2
Sergeant Major 2
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Has thanked: 1 time
Been thanked: 1 time

Fri Feb 09, 2007 5:36 pm

Well contrary to popular beief sch-40 doesn't designate a pressure rating it only tells of wall thickness. Your pipe needs tp say nsf-pw
Current project: Afghanistan deployment
Killjoy
Sergeant
Sergeant
Posts: 1052
Joined: Sun Nov 12, 2006 12:51 am
Location: New Mexico

Fri Feb 09, 2007 5:39 pm

or have a psi rating on it.
User avatar
Flying_Salt
Corporal 3
Corporal 3
Posts: 779
Joined: Mon Oct 09, 2006 4:57 pm
Location: Texas

Fri Feb 09, 2007 6:10 pm

You don't really NEED to get an air compressor. I use a bike pump for my pneumatic, and it works fine, but the piston starts bothering me at around 70 psi. Nice guns, a lot better than my first.
A modded sprinkler valve will help a lot. You will love it and want to marry it and name it George.
You live in Hawaii! You're my hero! Here in Texas its just bone dry and so flat spilled hot sauce won't go nowhere. Did you guys really get snow/ice down there a couple weeks ago?
sgort87 wrote: I hereby present Flying_Salt with The one and only <a href="http://www.geocities.com/sgort87/ghetto">Ghetto Award!</a>
Post Reply