Search found 62 matches

by boyce123
Mon Jul 09, 2012 12:21 am
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

just to clear things up, the valve doesn't leak at all...the valve itself didn't and doesn't have any leaks, there was just a pinhole starting to form through the jb weld plug (at my highest pressures)where the solenoid used to be, so i just decided to cap it to ensure that it wouldn't leak any furt...
by boyce123
Sun Jul 08, 2012 10:21 pm
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

ask jsefcik what that is, he is the one that modded the valve ( i added the cap because a small leak was forming as 130 psi, so i then had to add a longer nipple to make it fit, hence making it appear more ghetto :wink: ) the tennis ball is a good idea, i'll try it tomarrow morning.
by boyce123
Sun Jul 08, 2012 9:14 pm
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

... well... i haven't been able to find any foam that doesn't shoot straight into the sprinkler valve on the first shot (even through the 1/2 in hole in a rubber washer in the back) so i've just been using a few layers of rubber washer, the sanding drum is also rubber so it kind of provides itself a...
by boyce123
Sun Jul 08, 2012 6:43 pm
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

i know that the piston expands, it was relatively loose in the pipe before i expanded it out to the size were it seemed to perform best. The spuds aren't loading because the piston is sealing to well to the 'riding' surface, it only leaks through on higher pressures, as with filling (i load after th...
by boyce123
Sun Jul 08, 2012 3:28 pm
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

sorry jsefcik... i will get pics tonight, i'm on my lunch break now and i work all day...

I am just using the face of the sanding drum, it works great the way it is (with lots o lube)
by boyce123
Sat Jul 07, 2012 10:29 pm
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

i don't really prefer golf balls (as they ricochet really easily and have a higher potential of hitting something that shouldn't be hit), but i still use them alot, especially for distance shots. If i want to do damage to something, i make a wood plug and sometimes add a big lag bolt to make it more...
by boyce123
Sat Jul 07, 2012 4:56 pm
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

There is definatly a delay since i put the sanding drum on it (as it is much shorter than i designed the pilot for), but the delay in the video i think is from the ball valve opening relativly slowly. The added pilot volume will eventually be accounted for with a longer piston, but the sanding drum ...
by boyce123
Fri Jul 06, 2012 11:35 pm
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

i plan on getting the barrel support completed tomarrow, and mounted, but i ran into an issue than i'm not sure how to fix... if i try to load a perfectly air tight projectile (as a potato), it pressurizes the chamber instead of letting air out the pilot. I have the sprinkler valve on now, but even ...
by boyce123
Sat Jun 30, 2012 5:01 pm
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

if i end up making a big (thinking of making a massive 4 in chamber) i'll consider a bushing reducer. i blew out a seal today, so i have to get a thicker piece of rubber, and i might put a washer behind it to prevent further blowouts... so damage might take a while :(
by boyce123
Sat Jun 30, 2012 1:27 pm
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

the fitting is pressue rated, i can get a pic of it if you guys really want, i've seen other pneumatics with bell reducers and they didn't have issues either.
by boyce123
Sat Jun 30, 2012 8:52 am
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

the piston works great... most of the time. I do have a small lag bolt with a washer holding the sealing face on. The piston will work for now (i'll figure something else out after the fourth), but it certainly has issues with the singular, uneven o ring groove. I plan on having one turned eventuall...
by boyce123
Fri Jun 29, 2012 10:26 pm
Forum: Pneumatic Cannons
Topic: First pneumatic, 2" piston valve
Replies: 32
Views: 6450

First pneumatic, 2" piston valve

I got bored earlier this week and decided to try making a pneumatic. I decided to just go with a basic 1 1/2" T piston valve design (2" T with a 1 1/2" sealing face). This is the first pneumatic that i have made, and i'm fairly suprised by its performance thus far. I have been firing it at 130 psi, ...
by boyce123
Fri Jun 29, 2012 10:27 am
Forum: Pneumatic Cannons
Topic: piston help
Replies: 14
Views: 3293

i don't have a decent chuck to center it with, and i know someone who might turn it for me, just need to shell out for the raw material. I got it out today, and attatched a barrel for range testing. With the same length barrel, its launching similar, even farther than the big advanced combustion tha...
by boyce123
Thu Jun 28, 2012 5:58 pm
Forum: Pneumatic Cannons
Topic: piston help
Replies: 14
Views: 3293

the 1 1/4 end caps at my hardware store are squared off at the ends. i'll be working on the cannon tomorrow, i'll see if i can get some pics of what i come up with. EDIT: I just went out and cut an O ring groove in the wood... the seal ended up being to good (not letting any air into the chamber), s...
by boyce123
Thu Jun 28, 2012 1:15 pm
Forum: Pneumatic Cannons
Topic: piston help
Replies: 14
Views: 3293

i took the valve apart, it is a bit looser than i thought, but was tight enough that a layer of tape prevented it from going in. I never thought this would be a permanent piston, i only made this in an attempt to get the cannon done for the fourth on time (without having something machined). The cou...