Air Delay Mine

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.
PVC Arsenal 17
Staff Sergeant 3
Staff Sergeant 3
Posts: 1762
Joined: Mon Mar 27, 2006 4:18 pm
Location: United States

Sun Feb 04, 2007 9:44 am

I've been trying to come up with some sort of pneumatic mine for ages. It had to be small, cheap, easy to build, and the most challenging- it had to have a delay.

So I came up with this and finished it today. It cost $10 and wasn't really hard to build. Best of all, it actually works as intended!

It consists of a 2" plug and a 2" x 1/2" bushing glued into a coupling.
A short length of 1/2" pipe runs through the bushing to the inside of the chamber and is capped. The cap has a pin-hole through it. The pipe extends out of the large bushing into a 1/2" x 3/4" bushing which connects to a 3/4" union.

The idea is simple. You fill the mine through the schrader valve and it fills up. Slowly, air bleeds into the small 1/2" chamber until it ruptures a burst disc, thus firing some baby powder or whatever you put in it.

It does work, but I'm still experimenting with burst discs to find the balance between power and an appropriate delay.

Image

Image

Image

(more pics and hopefully a video soon)
User avatar
VH_man
Staff Sergeant 4
Staff Sergeant 4
Posts: 1827
Joined: Sat Dec 09, 2006 6:00 pm
Location: New Hampshire
Been thanked: 1 time

Sun Feb 04, 2007 10:27 am

OOOHHH. If You could put a pin in that it would be very useful for airsoft/paintball. Mabey even Nerf........ Im Definetly going to have to try this.
PVC Arsenal 17
Staff Sergeant 3
Staff Sergeant 3
Posts: 1762
Joined: Mon Mar 27, 2006 4:18 pm
Location: United States

Sun Feb 04, 2007 10:41 am

Mini nerf darts fit in there perfect.
User avatar
Bluetooth
Corporal 4
Corporal 4
Posts: 863
Joined: Tue Jun 27, 2006 7:57 am

Sun Feb 04, 2007 11:09 am

Cool. I want one.
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

Sun Feb 04, 2007 12:39 pm

For triggered actuation, you should try threading a long hook through the end of the main chamber and into the pin hole. Pressurize, unscrew a couple times, and it would start to let air into the smaller chamber. I mgiht have to try a couple of these. Glad you finally figured a simple design out.
PVC Arsenal 17
Staff Sergeant 3
Staff Sergeant 3
Posts: 1762
Joined: Mon Mar 27, 2006 4:18 pm
Location: United States

Sun Feb 04, 2007 12:42 pm

Brilliant idea with the hook!

Searching for the right burst disc is becoming a pain in the ass. I think wide electrical tape will work best.... not sure though.

But I did paint it! Image
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

Sun Feb 04, 2007 12:58 pm

Try 1/16" rubber, it bursts at exactly 80 psi, how high do you pressurize it?
Also, with the hook, you could have like six hanging down from your belt and/or various pockets, like in all the shoot-em-up movies.
PVC Arsenal 17
Staff Sergeant 3
Staff Sergeant 3
Posts: 1762
Joined: Mon Mar 27, 2006 4:18 pm
Location: United States

Sun Feb 04, 2007 1:15 pm

I've taken it to around 110 psi.
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

Sun Feb 04, 2007 1:34 pm

So the rubber would be pretty good, it's only $3 for a square foot, so you could get around 30 discs. See if you can get it at a local hardware store.

I'm going to make a couple of these, and experiment with diferent burst discs, different pin hole sizes for different times, etc. They could help with freaking people out on Halloween, considering how short the "barrel" is and all burst discs are frickin loud anyway. See someone coming up the street, pop in the rigth disc for the right time delay, load it up with flour, pressurize, and stuff it in a bush or something.

Another question, forget the variables, about how long does it take for the disc to rupture?
Aluminum Foil: ? seconds
Soda Bottle: ? seconds
Milk Jug: ? seconds
And whatever else you use for discs.
User avatar
StealthSpud
Private 4
Private 4
Posts: 81
Joined: Thu Jan 11, 2007 9:43 pm

Sun Feb 04, 2007 2:13 pm

That's really sweet and it's a simple design!
Might have to try that out!
User avatar
dippydodo03
Specialist
Specialist
Posts: 103
Joined: Tue Jan 23, 2007 5:11 pm
Location: michigan

Sun Feb 04, 2007 6:44 pm

i'm gonna try these in paintball. me and my friends are always looking for somenew challenge in paintball. :rr:
User avatar
dippydodo03
Specialist
Specialist
Posts: 103
Joined: Tue Jan 23, 2007 5:11 pm
Location: michigan

Sun Feb 04, 2007 6:45 pm

i like the paint job
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

Sun Feb 04, 2007 8:18 pm

There's an edit button if you forget to put something into your first post.
What would you shoot out of it in a paintball game?
User avatar
Bluetooth
Corporal 4
Corporal 4
Posts: 863
Joined: Tue Jun 27, 2006 7:57 am

Sun Feb 04, 2007 8:33 pm

Ummmm... Maybe paint but I'm just pulling that out of my ass :wink: .
User avatar
noname
First Sergeant 4
First Sergeant 4
Posts: 2698
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA

Sun Feb 04, 2007 8:35 pm

So I'm the dumbass now? Paint will just fly out when you chuck it, and there isn't enough space to get paint in there.
Post Reply