Search found 1731 matches
- Thu Sep 16, 2021 5:07 pm
- Forum: Ammo & Parts
- Topic: What caliber ammo is most available In 2021?
- Replies: 3
- Views: 9234
Re: What caliber ammo is most available In 2021?
Potato caliber, lime caliber, golf ball caliber, and soda can caliber are all readily available in my local area.
- Tue Sep 14, 2021 6:09 pm
- Forum: Hybrid Cannons
- Topic: Wires and Walls.
- Replies: 2
- Views: 4919
Re: Wires and Walls.
I've drilled holes and fed wire through an aluminum chamber and used epoxy to seal it. It's been 12 years and it still works. Another more recent cannon I made uses a spark plug. Drill and tap a hole and stick a spark plug in there. Well, the spark plug went through an end plate, not the chamber. Bu...
- Sun Sep 05, 2021 2:37 pm
- Forum: Hybrid Cannons
- Topic: MAPP Gas Safety
- Replies: 3
- Views: 4505
Re: MAPP Gas Safety
I'm no expert, but people have used MAPP gas for combustions and hybrids for a long time. There's no issue compressing MAPP gas in a metering pipe for fueling a cannon as long as it's a metering pipe and not some kind of tank where you add MAPP and AIR (or any form of oxidizer) for a pre-mixed fuel ...
- Mon Aug 30, 2021 5:48 pm
- Forum: Hybrid Cannons
- Topic: Thoughts on my piston valve design
- Replies: 41
- Views: 29822
Re: Thoughts on my piston valve design
Are the fittings aluminum? I'm not familiar with the fittings you are going to use. I also don't know why commercial fittings are given the pressure ratings that they have. With PVC it's obvious, but if galvanized iron says 150psi then that seems strange to me but I'm sure there's some reason. Maybe...
- Sat Aug 28, 2021 11:02 pm
- Forum: Hybrid Cannons
- Topic: Thoughts on my piston valve design
- Replies: 41
- Views: 29822
Re: Thoughts on my piston valve design
Based on your shown areas, I got 1143 psi chamber pressure for equalization, so the same that you got. It looks like this is an estimate though because it looks like you clicked the surfaces and there are chamfers on them, so the actual diameters will be a little larger, but it should be pretty clos...
- Thu Aug 26, 2021 2:53 pm
- Forum: Hybrid Cannons
- Topic: Thoughts on my piston valve design
- Replies: 41
- Views: 29822
Re: Thoughts on my piston valve design
Good to see you back. Designing is a big part of the fun, so I look forward to you working on it some more.
- Thu Aug 19, 2021 1:35 pm
- Forum: Hybrid Cannons
- Topic: Hybrid Piston Pilot Air Ratio
- Replies: 18
- Views: 13930
Re: Hybrid Piston Pilot Air Ratio
I thought the same thing about the piston. It looks machined for sure and very nice!
- Sun Aug 15, 2021 11:27 pm
- Forum: Off-Topic Hobbies
- Topic: I CAN HAZ MILING MACHIEN?
- Replies: 4
- Views: 8537
Re: I CAN HAZ MILING MACHIEN?
Very nice! That's a good way to bargain: twice the scrap rate. Looking forward to your progress on getting it up and running. Congrats!
- Sat Aug 14, 2021 3:50 pm
- Forum: Hybrid Cannons
- Topic: Hybrid Piston Pilot Air Ratio
- Replies: 18
- Views: 13930
Re: Hybrid Piston Pilot Air Ratio
Thanks for the explanation. Now I get it. Like you said, the o-ring isn't supported from the outside, so it stretches and just comes off the rod when you shoot it. I agree that a harder o-ring is the best experiment to try next. If all else fails, you can try to modify the valve with a sealing face ...
- Sat Aug 14, 2021 12:08 am
- Forum: Hybrid Cannons
- Topic: Hybrid Piston Pilot Air Ratio
- Replies: 18
- Views: 13930
Re: Hybrid Piston Pilot Air Ratio
Does the small o-ring pass over a port while under pressure? If so, it's like running the o-ring over a cheese grater. You might try a different shaped o-ring, such as the X shaped ones. They have much less friction when squeezed, but there would still be friction caused by pressure. They might work...
- Tue Jul 20, 2021 5:32 pm
- Forum: Pneumatic Cannons
- Topic: Rate my cannon
- Replies: 11
- Views: 7891
Re: Rate my cannon
Nice cannon. You're taking a significant risk by using PVC with that much pressure inside. It can fail within it's rated pressure for no apparent reason because it's plastic and it tends to be fragile. It won't just crack, split or tear, but it will fragment and explode in your face. Wear safety gog...
- Wed Jul 07, 2021 2:49 am
- Forum: General How-To & Discussion
- Topic: Hacksmith of potato guns?
- Replies: 6
- Views: 8119
Re: Hacksmith of potato guns?
Honestly I think people would be asking for different content pretty fast. Take note of the slingshot channel. It's called the slingshot channel, yet he does way more than make slingshots. He holds true to the basic concept by mostly using rubber for power. I'm not sure potato guns could be as diver...
- Tue Jun 29, 2021 8:53 pm
- Forum: Pneumatic Cannons
- Topic: Tennis ball launcher
- Replies: 3
- Views: 4208
Re: Tennis ball launcher
Very cool. I made a tennis ball cannon in high school from a rolled and welded sheet like that. It worked perfectly and I bet yours will too.
- Tue Jun 29, 2021 5:58 pm
- Forum: BB, Airsoft, and Pellet Guns
- Topic: Victorian "Air Cane" brought back to life
- Replies: 29
- Views: 26391
Re: Victorian "Air Cane" brought back to life
The damage video was fun to watch. This was a great project.
- Tue Jun 29, 2021 5:43 pm
- Forum: Hybrid Cannons
- Topic: Hybrid Piston Pilot Air Ratio
- Replies: 18
- Views: 13930
Re: Hybrid Piston Pilot Air Ratio
Is this a vented pilot design? I worked the numbers for an 8X mix and a 75% of maximum opening pressure for the piston. Same pressure in the pilot as the preignition chamber pressure. I get a pilot piston diameter of 16.73mm (assuming a 6.5mm piston diameter chamber side), so basically the same as M...