I guess the piston does not deal as good as I thought,

Thanks also mark ill try the white lithium grease or something similar. I guess I am getting too much blow by like you say, cause the chamber does fill rather quickly. I am going to try some teflon tape or maybe a later of electrical tape over ...

Ok I understand, however if you look a couple of posts up of mine of my ready cover idea, I placed the schrader valve on a t just above the pressure gauge in between the sprinkler valve and the main piston, this is the pilot area that your talking about correct?

So maybe the problem is I am not ...

I am not using felt as a bumper, the white bumper is 3/4" rubber and silicone.

What do you mean put a full valve in the breech ? What kind of fill valve ? Can you draw an arrow on one of the pictures to show me where your talking about ? Also I dont really understand how you use air pressure to ...

Ok guys all done with the piston. I sanded it all down, painted and sealed it after cutting the O-ring grooves. Put on the O-Rings. Greased it up REALLY good with Vasolene, put it all together and BOOM she fires. However after the first shot. I start pumping air back into it and it just goes i am ...

OK another quick one for the cosmetic Department. Anyone know of an idea if I wanted the finished cannon to have an almost seamless Barrel design to hide all the guts and valves on the back end ? I was thinking of cutting another piece of 4" pipe about 12 inches long to cover all the stuff on the ...

@ Warhead, Yea I can tip it but it is seating fine after I tried this trick, GREAT IDEA.

Because of installation imperfections on any Coax Cannon Place a circle of sandpaper and bolt it in front of a rubber neoprene cushon so it wont spin, bolt the whole assembly to the threaded rod and put the end ...

I Doubt it. I had to make a Rod and 2 pistons because of some short sightedness on my part. Already glued the barrel's and stuff so the Piston had too far to travel between the end of the male cap and the front of the barrel. Would be like 7 inches of travel for that 3'' coupler. Plus the Coupler ...

OK GUYS THANKS FOR ALL YOUR HELP. I did some trimming down on the pistons rubber gaskets, Lubed her up in some good ol vasolene. And cut the threaded Rod to size and pumped her up to 20 psi to test.

BOOOOOOM ! Put a Tennis ball about 140 Yrds down range. Paced it off.

Tried it again and was able ...

ok what kind of Lube did you use ? that doesn't make a too TIGHT of a fit ? you were still able to move the piston ?

The felt you glued around the outside diameter of the piston ?(around the circumference ?)

seems like there is barely enough room to get that thing in there, I think felt would just ...

The spring will not get smashed as it will be recessed in a little pocket created in the 2'' to 3/4'' reducer fitting. I measured it it should fit perfectly. As far as the Flow on the fill is concerned I am using a 20 gal compressor at 100psi, so I am guessing it must be the valve.

For HI, the ...

Oh Not Pictured but the sprinkley valve has been since modified with a blowgun attachment.

How do I use the innertubes for the sealing face ? glue them down in a circle around the diameter of the piston ?

I understand simpler is better. I will consider again, have in the past the ball valve ...

Sorry if I havent seen an earlier post where you might have described it. What are the Tail sections and Nose sections made from ? did you fabricate them yourself ? or salvage from something else ?

thanks

Ok so I am new to spud files and have been working on a typical COAX pneumatic design with a piston Valve. I am totally dead in the water and need some help

Using 4'' pipe for chamber
Using 2.5'' Pipe for barrel (tennis Balls for ammo)
3'' Coupler for Piston, with modified extension (kind of a ...