A series of newb questions

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.
Natex88
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Thu Apr 10, 2008 6:41 am

Okay I've been looking at spud guns for years, and now I've finally overcome my explosion fears enough to make one, although my girlfriend doesn't approve :P I've got a few questions I have to sort out, sorry if they've already been asked before though.

I live in the middle of a large city, so walking to a field with this gun in hand isn't really possible. The gun I'm building has a sniper rifle shape and is made from PVC, not copper. I was wondering, is it possible to make the stock, chamber+sprinkler valve and the barrel all detachable from each other, so I can put it in my bag and walk to where I have to go? Would there be safety concerns with doing this? The way they would disassemble is by unscrewing the threaded pipe, nothing more.

Also I see everyone modifies their sprinkler valves so they don't use the solenoid, why is that?

And finally, is it possible to use the stock as the chamber? Why don't many people do this? I wouldn't be taking the gun to incredibly high pressures, no higher than 100PSI.
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watto
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Thu Apr 10, 2008 6:47 am

Making a gun that could be disassembled shouldn't be that hard I look forward to seeing it. The hose on the sprinkler is to make the diaphragm open much quicker and so you don't need batteries to pilot it.

edit: welcome to spudfiles :P
Last edited by watto on Thu Apr 10, 2008 6:52 am, edited 1 time in total.
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psycix
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Thu Apr 10, 2008 6:51 am

If you take threaded adapters and a threaded sprinkler you can just unscrew the barrel, valve and stock from eachother.
Yes you can use stock as chamber though it may be more vulnerable this way if you drop it or put mechanical stress on it.
Till the day I'm dieing, I'll keep them spuddies flying, 'cause I can!

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bluerussetboy
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Thu Apr 10, 2008 7:05 am

1. Many of the modded sprinkler valve guns can be disassembled. Most sprinkler valves are threaded and not cemented together.

2.A quick search would've have resulted in far too many threads explaining why. Solenoids pilot too slowly. Blowguns will actuate faster even if you have some ungodly length of hose attaching them. Solenoids just can't exhaust the pilot volume fast enough. Use the search for a better explanation.

3. If you were to look through the pneumatic showcase you would see many launchers using the stock as a chamber. You would also see comments like 'OMG it could explode in your face' or 'it's not efficient'. The truth is that no matter where your chamber was it could explode from sharp hits, poor soldering/solvent welding, over pressurization, or just plan carelessness. As for the efficiency, try to make your stock air chamber with the least amount of complicated bends and unnecessary tees. If you have to use tees try to prevent crossover pipes or additional chambers. One main chamber with as few bends as possible should yield good results.
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Jared Haehnel
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Thu Apr 10, 2008 8:35 am

It would be pretty easy to build a gun that would unscrew and be reasonably portable the down side it its added cost and work...

I think the dangers of PVC exploding in your face are minimal given you use REASONABLE pressures. And if any one is truly concerned it. An pair of odd denim jeans wrapped around the chambers would contain the plastic shrapnel in the event of catastrophic failure...

You'd better off making a piston valve it would increase your power significantly...
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watto
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Thu Apr 10, 2008 8:37 am

I agree piston cannons are cheaper more powerful and more fun to build. I wouldn't have thought denim would contain the pvc shrapnel...someone should test it
:idea:
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bigbob12345
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Thu Apr 10, 2008 8:55 am

An pair of odd denim jeans wrapped around the chambers would contain the plastic shrapnel in the event of catastrophic failure...
It has been tested and all it did was make the explosion more violent.
It doesnt stop the shrapnel at all the explosion just rips it away and for some reason the shrapnel gets faster and the explosion more violent
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Hubb
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Thu Apr 10, 2008 8:58 am

If not mistaken, it was tested....and failed. Just use the reasonable pressures and plenty of teflon tape and go for it. Also, for now, I would just stick with the sprinkler valve. If you've never built a pneumatic before, you should be impressed with its results.
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watto
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Thu Apr 10, 2008 8:58 am

Just as I suspected :D
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Jared Haehnel
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Thu Apr 10, 2008 9:13 am

An pair of odd denim jeans wrapped around the chambers would contain the plastic shrapnel in the event of catastrophic failure
What pressures did they test it at?....huh learn something new every day...
My current projects....

Currently buying part for...
http://www.spudfiles.com/forums/my-new- ... rt,15.html
Still on the drawing board...
C02 tank hybrid
Screen doors for submarines...
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bigbob12345
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Thu Apr 10, 2008 9:15 am

I dont know but ill go see if i can find a link
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starman
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Thu Apr 10, 2008 10:18 am

Natex88 wrote:Okay I've been looking at spud guns for years, and now I've finally overcome my explosion fears enough to make one, although my girlfriend doesn't approve :P I've got a few questions I have to sort out, sorry if they've already been asked before though.

Also I see everyone modifies their sprinkler valves so they don't use the solenoid, why is that?
On the sprinkler, you can keep the solenoid and activate electrically if you want, however, your performance will suffer....but then, everyone's already said that.

On the girlfriend thing. It's good that you aren't being cowed into girl-think compliance on this. If you were building one of those idiot milk-jug and paper towel tube "spudguns" I would agree with her.

I've said this before, a well built, high performance, well presented spud gun is an amazing chick magnet. Even suspicious girls will watch curiously from a distance. Most will be right there watching you. Some will want to shoot it too!

So, take your time, do your homework and build a nice gun that fits your needs. There's plenty of options in the hobby that will allow that. You won't be sorry. Welcome to Spudfiles!!

Edit: Dang, Hubb beat my edit...
Last edited by starman on Thu Apr 10, 2008 10:40 am, edited 3 times in total.
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Hubb
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Thu Apr 10, 2008 10:30 am

I've said this before, a well built, high performance, well presented spud gun is an amazing chick magnet. Even suspicious girls will watch curiously from a distance. Most will be right there and want to shoot it too!

So, take your time, do your homework and build a nice gun that fits your needs. There's plenty of options in the hobby that will allow that. You won't be sorry. Welcome to Spudfiles!!
Seconded.

Example: My latest combustion launcher. My wife frowned upon me, saying she saw no need for it, that is, until I built it. She said I looked sexy holding the thing and she insisted I let her shoot it.
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D_Hall
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Thu Apr 10, 2008 11:11 am

*sigh*

My wife just rolls her eyes at my guns.

Note to self: Find girlfriend who doesn't make her living with explosives. :D
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Jared Haehnel
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Thu Apr 10, 2008 11:33 am

Note to self...

It is possible to find girls who likes to play with explosives....Just keep looking...
My current projects....

Currently buying part for...
http://www.spudfiles.com/forums/my-new- ... rt,15.html
Still on the drawing board...
C02 tank hybrid
Screen doors for submarines...
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