Search found 79 matches

by whoa044
Tue Sep 28, 2010 3:02 pm
Forum: Hybrid Cannons
Topic: 10X Hybrid golfball launcher
Replies: 87
Views: 22373

If anybody actually has HPA tanks, whether it's small paintball tanks, or industrial tanks, you can easily build something that tests burst disk pressures. An inlet, a high pressure gauge, and union are all that's needed.

Simply put, get a tee, and put a gauge and union on it.
by whoa044
Mon Sep 27, 2010 10:17 pm
Forum: Hybrid Cannons
Topic: Hybrid Barrel Explosion
Replies: 16
Views: 4751

The gun will be expected to fire at up to 15x mixes, possibly 20 if I have faith in the 2" forged steel pipe. At 10x HGDT calculated barrel pressures to be 1000psi +/- 50, depending on how strong the burst disks are. Thanks for the suggestion on aluminum. Is sch 10 safe enough to go at these pressur...
by whoa044
Mon Sep 27, 2010 7:59 pm
Forum: Hybrid Cannons
Topic: Hybrid Barrel Explosion
Replies: 16
Views: 4751

Hybrid Barrel Explosion

No actual barrels exploding, sorry. I was interested in knowing what kind of barrels you guys use. Currently, my only option is copper. It's light, and can be bought in long sections. Anything plastic is out, since I'm guessing it'll shatter into a thousand pieces. HGDT shows pressures in the barrel...
by whoa044
Sun Sep 26, 2010 8:13 pm
Forum: Hybrid Cannons
Topic: Barrel diameter size tolerances
Replies: 18
Views: 3304

I hope this pipe dimensions chart helps with what you are looking for. If you don't already have a pair of calipers, buy them. I used to have a few glowsticks, 14" long, and 0.585 inches thick. I considered a 1/2 inch (0.622) pipe good enough to shoot them from. What I consider a perfect fit, is som...
by whoa044
Sun Sep 26, 2010 3:16 pm
Forum: Hybrid Cannons
Topic: 2" Union Burst Disks
Replies: 20
Views: 4806

Yeah I figured that's what I would do. It seems tapered steel pipe will be easier (and a little more consistent) to make a sharpened edge
by whoa044
Sun Sep 26, 2010 12:55 pm
Forum: Hybrid Cannons
Topic: 2" Union Burst Disks
Replies: 20
Views: 4806

Good idea. Shouldn't be any trouble, except making sure that that is matches the diameter of the union. I'm assuming you also use 2" unions?
by whoa044
Sun Sep 26, 2010 9:27 am
Forum: Hybrid Cannons
Topic: Spark Plugs
Replies: 11
Views: 3001

That's if you use suzuki dr 250 spark plugs.
You can find adapters for 14mm spark plugs, if you don't want too many bushings to go from a 1/8 inch spark plug.
by whoa044
Sun Sep 26, 2010 9:24 am
Forum: Hybrid Cannons
Topic: 2" Union Burst Disks
Replies: 20
Views: 4806

Yeah, rubber splits, rather than just falling apart like thin metal.
Does anybody know where I can get 2" circular punches?
by whoa044
Sat Sep 25, 2010 10:35 pm
Forum: Hybrid Cannons
Topic: Fueling with pump
Replies: 18
Views: 5877

I think the only place where there should be mixed fuel and air is inside the combustion chamber. Anywhere else is dangerous. Just like having a premixed tank of oxy and acetylene. That would be exagerating it, but since the shock pump has a very small volume, and can contain some high pressures, I ...
by whoa044
Sat Sep 25, 2010 9:46 pm
Forum: Hybrid Cannons
Topic: 2" Union Burst Disks
Replies: 20
Views: 4806

Or I could just wait a few days. If it isn't tapered, then I guess I'm all good, only need a rubber washer. I'm thinking of buying a few 1/4 thick neoprene squares, and then cut disks out using an X-Acto knife. That just gave me a great idea: Instead of using rubber to make seals in the union. Could...
by whoa044
Sat Sep 25, 2010 11:23 am
Forum: Hybrid Cannons
Topic: 2" Union Burst Disks
Replies: 20
Views: 4806

I ordered a 2" 2kpsi union from Murray Equipment Inc just a two days ago.

Would it be possible to just grind off the barrel side of the union, so the other tapered side holds the gasket? Or if both sides are grinded off, the pipe on the chamber side will hold the gasket inside the union.
by whoa044
Sat Sep 25, 2010 9:43 am
Forum: Hybrid Cannons
Topic: Spark Plugs
Replies: 11
Views: 3001

Please don't modify the threading on anything -_- If you want 10x mixtures, what would happen if you screw up? I was hoping I'd get to post a little earlier, but here it goes: You can find spark plug to NPT adapters here . From there, I'm sure you could use a bushing if you need a larger size than 1...
by whoa044
Sat Sep 25, 2010 12:25 am
Forum: Hybrid Cannons
Topic: 2" Union Burst Disks
Replies: 20
Views: 4806

Do all unions have tapered faces? What's required is to make the inside surface level, and to have a gasket on both sides of the disk? Would it be safe to glue the gasket to the union? Thanks so far btw
by whoa044
Fri Sep 24, 2010 11:51 pm
Forum: Hybrid Cannons
Topic: 2" Union Burst Disks
Replies: 20
Views: 4806

2" Union Burst Disks

I was wondering, since I never got the opportunity to test out a soda can cutout to see its bursting pressure, has anybody ever done so with a 2" union? The new hybrid design will be a large 2" hybrid. I've heard that problems may arise when so many burst disks are required. It's been told you must ...
by whoa044
Fri Sep 24, 2010 4:15 pm
Forum: Hybrid Cannons
Topic: New fuel/air injection method?
Replies: 18
Views: 3764

Never thought of syringes. Maybe a large volume syringe, with a flexible tube leading from a hole in the side towards the back for fuel injection, and a hose at the "needle" going into the chamber.

Would have to account for tube volume, if you really want to get accurate.