2'' Piston 1.5inch Porting finaly done

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
User avatar
elitesniper
Sergeant
Sergeant
Posts: 1090
Joined: Sat Oct 13, 2007 8:40 pm

This is my 2 inch piston 1.5porting i have finaly completed the piston is a 1 1/4 coupler sealing face is a toliet plunger rubber, i have tested this only at 20 psi and it seals great. piston is service able through the back threaded plug piloted by a 1inch sprinkler ,and filled by a QC, no chamber yet cause i need to ask my teahnology teacher for it :D
Attachments
piston open
piston open
piston sealing against the barrel
piston sealing against the barrel
pistonside2.JPG
piston2frontside.JPG
front2piston.JPG
side of the piston
side of the piston
User avatar
DYI
First Sergeant 5
First Sergeant 5
Antigua & Barbuda
Posts: 2862
Joined: Sat Jul 07, 2007 8:18 pm
Location: Here and there

It looks like the piston head is a smaller diameter than the sealing face. I would assume that this isn't the case because you've already piloted the valve successfully, but the picture looks misleading. Very clean construction, and I look forward to seeing it on a launcher.
Spudfiles' resident expert on all things that sail through the air at improbable speeds, trailing an incandescent wake of ionized air, dissociated polymers and metal oxides.
User avatar
elitesniper
Sergeant
Sergeant
Posts: 1090
Joined: Sat Oct 13, 2007 8:40 pm

don't ask in somebody else's topic lol, dyi the piston/sealing face is like a fingernail larger then the barrel
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

DYI wrote:It looks like the piston head is a smaller diameter than the sealing face. I would assume that this isn't the case because you've already piloted the valve successfully, but the picture looks misleading. Very clean construction, and I look forward to seeing it on a launcher.
It looks that way possibly because the valve is upside down, so the piston is resting on the inside of the top of the tee, making it look smaller then the barrel.

Just a thought.

Edit: Going by this picture
Image


Oh and very nice elitesniper, looks great, good that you worked out the interhcangeable barrels thing. :)
Last edited by MrCrowley on Mon Jan 21, 2008 11:08 pm, edited 1 time in total.
User avatar
elitesniper
Sergeant
Sergeant
Posts: 1090
Joined: Sat Oct 13, 2007 8:40 pm

piston is just about the same size ad the barrel i finger nail bigger though :lol: , nice piston? pilot volume is alot but eh the 1inch sprinkler takes good care of that :twisted: ,Mr.C i finaly made my piston have inter chageable barrels though :D , now i can hear the BOOM!
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Haha yeah see my edit.

Pilot volume isn't all that bad, if your piston is longer then it looks. But yeah the sprinkler takes good care of that.
User avatar
elitesniper
Sergeant
Sergeant
Posts: 1090
Joined: Sat Oct 13, 2007 8:40 pm

oh that the piston is just tilting down cause i havent added the 2 inch tube yet haha the piston isn't connected :D i was so excited i just posted it , once the 2'' is on then the piston will be allined. with the barell.[/list]
User avatar
mark.f
Sergeant Major 4
Sergeant Major 4
Eritrea
Posts: 3643
Joined: Sat May 06, 2006 11:18 am
Location: The Big Steezy
Has thanked: 58 times
Been thanked: 62 times
Contact:

Agghhh... fights... ADD....

I will finish my current project before I build another piston valve. I will finish my current project before I build another piston valve. I will...

Nice piston. What type of bushing is that on the front of the tee, though? The head looks a little thin.

Put it on a cannon, though, as this is the cannon showcase... :wink:
User avatar
pizlo
Corporal 3
Corporal 3
Posts: 783
Joined: Fri Dec 22, 2006 7:27 pm
Contact:

Or if you dont want to put it on a cannon ship it to me and I will.
User avatar
elitesniper
Sergeant
Sergeant
Posts: 1090
Joined: Sat Oct 13, 2007 8:40 pm

why would i make a 2'' valve and not put it on a cannon? markfh11q, its a nsf-pw 2'' x1 1/2'' bushing its not actually thin quite think actually. im picking up the 2'' pvc on friday :lol: , barrel will be :lol: 4feet long chamber will be 34inches long :twisted:
User avatar
mark.f
Sergeant Major 4
Sergeant Major 4
Eritrea
Posts: 3643
Joined: Sat May 06, 2006 11:18 am
Location: The Big Steezy
Has thanked: 58 times
Been thanked: 62 times
Contact:

Why not make a longer barrel? Most of my barrels are at least five feet or longer, (6' is a common size), especially when building pneumatics.

You can also make a golfball barrel by sleeving in some SDR-21 with duct-tape spacers around the outside, then epoxied in place. My friend has a 10' barrel like this that hasn't let us down yet. No need for expensive SCH-80.

Your next logical step for your next piston valve is to make it both more powerful and look cleaner. The way to do this is to make the entire valve fit into a single tee with no external fittings. That way, if somebody looks at the valve from the side, it looks like just a PVC tee lying there. This both cuts down on pilot volume, make your tolerances a little tighter for enhanced performance, (you're forced to make a piston that actually fits and seals decently in your carriage pipe), and brings the looks factor way up. I made one of these for our robotics robot, (to make a t-shirt cannon to mount on it), but sadly, we haven't gotten around to finishing that. I think I'm gonna remake that valve anyway, being that it it only has 1" porting. What if we have to launch shirts in the Astrodome? :wink:
User avatar
elitesniper
Sergeant
Sergeant
Posts: 1090
Joined: Sat Oct 13, 2007 8:40 pm

nah man 4 feet is way to much for me i don think a foot more would make any perform mance worth noticing
chrissilvermancs
Private 4
Private 4
Algeria
Posts: 67
Joined: Sat Mar 07, 2009 2:18 am
Location: dd
Contact:

...........
Last edited by chrissilvermancs on Mon Jun 07, 2021 11:58 pm, edited 1 time in total.
User avatar
mark.f
Sergeant Major 4
Sergeant Major 4
Eritrea
Posts: 3643
Joined: Sat May 06, 2006 11:18 am
Location: The Big Steezy
Has thanked: 58 times
Been thanked: 62 times
Contact:

Chris, just tape off your fittings with masking tape to control getting the primer everywhere, and then other than that just let gravity control it.
Post Reply

Create an account or sign in to join the discussion

You need to be a member in order to post a reply

Create an account

Not a member? register to join our community
Members can start their own topics & subscribe to topics
It’s free and only takes a minute

Register

Sign in

  • Similar Topics
    Replies
    Views
    Last post