Search found 31 matches

by garybdavis
Tue Jan 15, 2013 9:56 am
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

Here is a pic of the hot wire foam cutting table I built to create the foam layout. Every custom cannon deserves it's own custom case!
by garybdavis
Tue Jan 15, 2013 9:43 am
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

Thanks for the compliment. I haven't built a golf ball barrel yet. Seeing how far the foam stress ball goes, I'm afraid of what I might do with a golf ball! I did get side tracked doing the custom foam layout for it's case. I built a hot wire foam cutting table for that. Oh, and I did add a needle v...
by garybdavis
Mon Dec 10, 2012 12:05 pm
Forum: General How-To & Discussion
Topic: Source for Black Teflon Tape
Replies: 4
Views: 2350

Source for Black Teflon Tape

Looking for a good on-line source for the "black tatical tape". Some of the paint ball places sell it, but it seems to be really expensive. Anyone know of a good cheap source?
by garybdavis
Fri Nov 30, 2012 11:41 am
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

I thought I might build a barrel for golf balls next - just for fun. :D The 3" barrel will shoot a plastic (vinyl) football (american football that is) 100'. Funny thing is I have to just stuff it in the end of a 14" barrel to get it to really fly. If I place it all the way inside the barrel (next t...
by garybdavis
Thu Nov 29, 2012 8:48 am
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

I did a test last night. Filled the 48ci bottle to 3kpsi and shot t-shirts at 200psi. Average range was just over 100' with a nice, high arc. Care to guess how many shots I got off before the bottle went below 200? Survey says.........48 I was hoping for 40 so I was pleased. Time for final breakdown...
by garybdavis
Tue Nov 27, 2012 4:03 pm
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

Update: 1. The slide valve worked very well, but newbies had trouble with it. So, I modified a blow gun for the pilot and added a push button for the pressure chamber fill. 2. Standard plumbing replaced with a custom machined manifold on the pilot side of the QEV. It integrates the blow gun pilot, g...
by garybdavis
Mon Nov 19, 2012 10:28 am
Forum: Pneumatic Cannons
Topic: Burst Disc 400-500 PSI?
Replies: 3
Views: 1670

If they just don't make the non-servicable burst discs in that range (I love their compactness), I'll use the Palmer adjustable pressure relief valve. Thanks for the link. I'm placing two 1/8 NPT ports in my pressure chamber: one for the relief valve and one for a bleeder valve. This is so I can ble...
by garybdavis
Sun Nov 18, 2012 7:36 pm
Forum: Pneumatic Cannons
Topic: Burst Disc 400-500 PSI?
Replies: 3
Views: 1670

Burst Disc 400-500 PSI?

I'm looking for one of those burst disc you see on the CO2 and HPA valves. You know, the small hex head that are 1/8NPT (I think). I see them all over the place that are 1.8k to 7.5k PSI, but none in the 400 to 500 PSI range. I've found regular popoff relief valves in 300 PSI in both 1/8 and 1/4 NPT...
by garybdavis
Thu Nov 15, 2012 5:07 pm
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

What's WIP? :? I replaced my welded up pipe with a 4" galvanized nipple, cap and reducer bushing. I get 100' to 125' shots at 200psi with it. That's about the range I need. I got over 20 shots with it at 1800psi in the HPA tank (my scuba tank is getting low...). That's enough efficiency for me. I re...
by garybdavis
Thu Nov 15, 2012 11:07 am
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

Any home welded pressure tanks (the elbow and chamber) should be hydrostatic tested. I assume any of the places that test scuba tanks will test my home made pressure chamber? What pressure do you have them test it to (I plan on running 300psi max)? The other two I can see are to use threaded pipe a...
by garybdavis
Thu Nov 15, 2012 9:04 am
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

I don't like the elbow which attaches the tank to the reg. It's unsupported and potentially can have a lot of stress put on it, I would consider an external structure that doesn't make it bear all the load. Otherwise, looks great! Yes, the 1/8NPT connections to/from the regulator make for a weak ph...
by garybdavis
Wed Nov 14, 2012 4:11 pm
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

Got my slide valve and Palmer regulator in. The silder really made a difference in the piloting of the QEV. At 200psi, I'm shooting 120ft or so with a nice arc. I'm not completely happy with the layout, so I may remote mount the tank with a hose. The barrel is 14"x2 1/2 EMT with a custom welded moun...
by garybdavis
Sun Nov 11, 2012 10:03 pm
Forum: Pneumatic Cannons
Topic: Oil Filled Gauge or Pressure Subber?
Replies: 3
Views: 1646

Oil Filled Gauge or Pressure Subber?

The pressure gauge mounted on my pressure chamber will go from full pressure to zero rather rapidly when the cannon is fired. I wonder if this will be hard on the gauge and cause it to fail prematurely. I've used oil filled gauges in applications where I had engine vibrations but not pressure snubbe...
by garybdavis
Fri Nov 09, 2012 9:28 am
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

Cobbled up a few parts and did a couple of tests. Can shoot a 220gm t-shirt 80 ft at ~160psi. The pressure chamber is a 3'x3/4" piece of pipe (what I had lying around the shop). The barrel is 2 1/2" EMT x 14" long. The only thing I've manufactured so far is the barrel. I turned a plug from a 1/8" th...
by garybdavis
Wed Nov 07, 2012 4:44 pm
Forum: Pneumatic Cannons
Topic: First Design, T-shirt Cannon, feedback on my initial design.
Replies: 55
Views: 16494

Enough research. Time to grab the safety glasses and start testing a few ideas... :glasses7: