Page 1 of 3

Need better pilot valve

Posted: Mon Apr 12, 2010 8:34 pm
by spudkpi
SO here is my gun

http://www.spudfiles.com/forums/the-1-4 ... 20693.html


...but I need a pilot valve or a way to modify the blowgun so that its works better at higher pressures. The blowgun keeps getting like jammed up or something.... Please help if you can. Much help appreciated.... I would like it to shoot semi-auto at about 500psi but I'm also struggling with the semi auto part. Hints and ideas welcome :idea:

Posted: Mon Apr 12, 2010 8:47 pm
by Lockednloaded
for semi auto get a simple push button 3-way valve. I think POLAND_SPUD has taken them to some pretty high pressure

Posted: Mon Apr 12, 2010 8:57 pm
by MrCrowley
What do you mean by the blowgun keeps getting jammed up? Some will work at high pressures, some leak. Luck of the draw it seems. You can try modding it for higher flow but you risk damaging it and at high pressures I think there is a risk it will leak.

For semi-auto, use a 3-way DCV (directional control valve). See this thread. By the way, you should shorten the nipple between chamber and valve on your cannon. It'd look better that way.

Posted: Mon Apr 12, 2010 11:16 pm
by jackssmirkingrevenge
A simple ball valve like brian used here will be good for any pressure you can throw at it without influencing opening load, if you want semi auto you can always spring load it to return to the closed position.

Posted: Tue Apr 13, 2010 2:39 am
by chinnerz
i agree, just go down to your local hardware shop and pick up a 1/4'' ball valve.

you can mod it a little by take the little lips of so that it can freely rotate 360*. then put on end in a drill and have it spin at like 100 rpm for 15 mins. this will loosen it up a bit, but not soo much that it will leak in the future. (just make sure it doesn't get too hot) then maybe spring load it ?!?! just an idea. that should cost me $7.50, which isnt too much and its probably alot cheaper in the USA

Posted: Tue Apr 13, 2010 5:20 am
by Matt_NZ
chinnerz wrote:i agree, just go down to your local hardware shop and pick up a 1/4'' ball valve.

you can mod it a little by take the little lips of so that it can freely rotate 360*. then put on end in a drill and have it spin at like 100 rpm for 15 mins. this will loosen it up a bit, but not soo much that it will leak in the future. (just make sure it doesn't get too hot) then maybe spring load it ?!?! just an idea. that should cost me $7.50, which isnt too much and its probably alot cheaper in the USA
So, did you do this, what was the improvement like after 15mins.

Posted: Tue Apr 13, 2010 5:32 am
by Crna Legija
you could use a pressure washer handle

Posted: Tue Apr 13, 2010 5:47 am
by chinnerz
Matt_NZ wrote:

So, did you do this, what was the improvement like after 15mins.
Yeah i did this at a friends place... It gets rid of that new ballvalve stiffness in the first 30sec... And after that the next 10 mins we didnt see a huge jump, but in the last 5 it got quite nice :D and it was still good till 130 which is the max we can get with a cheap pump

Posted: Tue Apr 13, 2010 3:44 pm
by Gun Freak
My 1/4 ball valve is amazingly easy to turn, with just one drop of 3in 1 oil on each side of the ball.

Posted: Tue Apr 13, 2010 3:46 pm
by jackssmirkingrevenge
Gun Freak wrote:My 1/4 ball valve is amazingly easy to turn, with just one drop of 3in 1 oil on each side of the ball.
I would recommend such lubrication over extensive drill-spinning in order to preserve the integrity of the seal, especially for higher pressures.

Posted: Tue Apr 13, 2010 3:53 pm
by Gun Freak
And I'm sure this would work even better... its insanely easy to turn. Don't bother doing all the work will drilling and sanding the lip and crap, just lube it.

Posted: Tue Apr 13, 2010 5:09 pm
by spudkpi
Wait... I'm sorry I don't get this but what ball valve and where located on the cannon. Does this solve my semi-auto problem? Right now as shown in the video I regulate the co2 to 500 then open a 3/8" ball valve into the chamber, then I close the ball valve and pilot the cannon. It works good for the most part I just want to be able to make it like semi-auto... pow... pow...pow type of thing :lol: . I need a barrel too :( .

Posted: Tue Apr 13, 2010 7:55 pm
by chinnerz
we are talking about getting rid of that blow gun and adding a ball valve to make a powerful single shot rifle

Posted: Tue Apr 13, 2010 8:09 pm
by clemsonguy1125
I think the ball valve will work good and wont give you many problems. Ive used ball valve to pilot all my piston valves and have had good preformance

Posted: Tue Apr 13, 2010 8:50 pm
by chinnerz
i think a ball valve is the best for pilots (sept using a a qev or something like that) for the price, but no semi automatic, unless you put a spring behind the piston and have the ball valve spinning on the end of a drill :D