Simple over/under tennis ball launcher

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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saefroch
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Sun Jul 17, 2011 11:16 am

Your valve has an incredibly low flow coefficent... are you sure that's correct? It may be, but I've little experience with sprinkler valves indeed. The inner diameter should be zero unless this is a coaxial, and the outer diameter should be the inner diameter of the pipe, that is to say the outer diameter of the space inside the pipe.

Even with these changes, I am still getting higher muzzle velocities with a larger dead space.
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tony48
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Tue Jul 19, 2011 4:18 pm

If you're still looking for 2.5" fittings, try to look up a Local plumbing supply place. If you can't find them there then order from flexpvc.com. They have great prices and a massive selection. If you manage to need something they don't have (i did) then email them and they will probably have it. You can also order 2.5" thinwall pipe and shipping is very well priced. I love this site.
If life gives you lemons, put them in your cannon and shoot them back at life!
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Technician1002
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Tue Jul 19, 2011 6:47 pm

A source for fittings is a good electrical supply place. Sched 40 non metallic conduit (PVC) has the same dimensions as the water pipe cousin. Non Metallic electrical conduit is grey instead of white.
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yman
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Wed Jul 20, 2011 9:55 am

tony48 wrote:If you're still looking for 2.5" fittings, try to look up a Local plumbing supply place. If you can't find them there then order from flexpvc.com. They have great prices and a massive selection. If you manage to need something they don't have (i did) then email them and they will probably have it. You can also order 2.5" thinwall pipe and shipping is very well priced. I love this site.
Thanks for he info - I came across them while searching online, although I ended up ordering from someone else (their site was a little difficult to navigate). Anyway - will keep them in mind in the future!
yman
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Wed Jul 20, 2011 9:56 am

Technician1002 wrote:A source for fittings is a good electrical supply place. Sched 40 non metallic conduit (PVC) has the same dimensions as the water pipe cousin. Non Metallic electrical conduit is grey instead of white.
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Didn't realize that - good to know! Being Sced 40, I assume it is also pressure rated like the water pipe?
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