ok, i get it now. now i need som guidance as to building a better piston.

im still confused about what you're telling me but what i believe you are trying to show me is that i need the extra room around my pistonfor that flashing yellow part in the diagram on page 5.

sooooooooooo, is this the death sentence: i need to duplicate all i have exept for the barrel diameter? its not so bad considering that i spent 30 dollars on it and some of that went to 5' of 3" pipe and 10' of 1.5" pipe.

2"pipe,,,,,,,,,,,,,,

soooo, are you saying i have to start all over?

yes it is a 2" tee, not sure what you mean by "porting" but the barrel and pipe connecting the tee to the threaded female adapter are also both 2" pvc.

well, first of all, know that the spring wasn't strong enough or even long enough to hold the valve shut, also, the rear piston had about 2-3mm of wiggle room in the 2" pvc pilot chamber. Also, remember that i need a new piston anyway because the end of that bottle broke.

thanks. Ok, first of all, does the rear of the piston need to be sealed in the body of the pilot chamber?

oh, i already did it. My valve didnt fire though. Also, my piston eventually broke alfter i already tested it. Could you guys help me with a stronger piston? Also, can you help me figure out why my piston valve didnt work, here's a diagram of it. http://i516.photobucket.com/albums/u323/kaianuanu/pis...

do you guys think 2 hours of letting the cement set is enough before giving it 150psi?


PS: never mind, my cement said 2 hours.

Thanks alot you guys, especially "thedeathofall". also, if i need a better pilot, i can put the blowgun back onto a 3/4" modded sprinkler valve. Also, remember that this is going to be SEMI-AUTO Anyway, this is how far i am now.

thanks, i just got back from the hardware store w/ some 3" PVC and im about to finish the chamber and then my piston valve will be ready to test!!! (after the glue sets for a few hours of cousre)

Ok, so here is an update on the progress i have made on my semi auto tennis ball launcher. I will have more done by tonight. im dying to tenst my piston valve now. you can see my pilot valve it a blowgun w/ a PVC grip. I still have to: -finish the 3" chamber -build the entire blowforward, hopper, an...

i went to home depot and changed back to the piston.

i have a question about the blow forward, The pison in it doesn't have to be sealed tight, right?