DSTV - Save the birds, ban the (blow)guns

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.
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dongfang
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Sun Aug 12, 2007 7:17 am

Hi,

Yes, I have added the valve to a cannon. That's why I have been away for a few days - my shooting range is 1200 km from my home :o

It triggers my gun to a much more powerful shot than my RainBird and blowgun assembly (but the blowgun is on a hose - it might have some improvement potential). I can really recommend trying to build one, for anyone who is not sure his/her piston valve is performing optimally.

There are 2 little flaws in the design (the valve on the pictures): At > 6 bar / 100 psi, it blows the o-ring off the pull-out piston. The piston should be made a little longer, or a larger o-ring should be used. And, when firing it with a good, hard pull on the cord, sometimes I pull the whole bolt out of it, and ruin the return spring. A stop of some kind should be added.

Again, this valve was only a substitute for a miniature DFTV (Darn Fast Turbo Valve, a 3-disk valve that was designed by someone else, a long time ago) to use as a trigger. The DFTV would still have been nicer.

Regards
Soren
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spud yeti
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Sun Aug 12, 2007 10:09 am

Hmm, a stop does sound good to retain the bolt. Perhaps a disk with lots of holes in it would work the best?

Can you not cut the O-ring groove deeper and use a thicker O-ring? Or epoxy it in :D

It sounds really great though, and I wouldnt mind seeing a setup of the whole cannon some time.
really good quote/phrase here
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Modderxtrordanare
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Sun Aug 12, 2007 11:40 am

I was going to say superglue the o-ring in and that should solve it slipping at 6bar+
Spudding since '05. Proud waster of plumbing and plumbing accessories.

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