SpudFiles

I read the 'piston valve explained visually' and i didn't understand
it so much, so i build plans for my first piston valve, so please
tell me if the piston in the plans will work good..

there are better ways... give my your email address and ills end you an email with an attached diagram

ok, i'll send you in a private message..
but i need more people to reply..

http://www.spudfiles.com/forums/piston- ... 16315.html

I wrote an explanation here, it's about halfway down. I hope it helps

Pilgrimman wrote:http://www.spudfiles.com/forums/piston- ... 16315.html

I wrote an explanation here, it's about halfway down. I hope it helps

ok, thank, i read it..
but the one i made in the plans should work either, right?

It might work, but frankly, there isn't enough detail in the drawing to tell. You might be better off with a co-axial design. It's the simplest iteration of a piston gun, and it is still powerful and compact.

I hope my email helped

john bunsenburner wrote:I hope my email helped

well, it did..
but, any ideas what can i use as a piston..

what tools do you have and how much money are you willing to spend... oh and what materials can you get/do you like to work with?

well, i have about 40$ to spend..

OK the best was is to use a deo can half cut of and filled with hot glue about half way. a piece of rubber on one end and one on the other (bumper and sealing face). simple. other wise use a pvs pipe with two end caps and O-rings or rubber as well

Interesting take on the piston valve design, if I understood it correctly then the ball valve is physically holding the piston in place and when it's fully opened, the piston goes through the valve.

It should work and work better in terms of opening speed than normal pistons because the pilot volume pressure is effectively zero, so piston acceleration is much more rapid. This means that you also need some form of spring and bumper to ensure your piston doesn't shoot out of the end cap.

The major "complication" I can see with this design is that the piston needs to be 100% airtight, so o-rings are a must.

john bunsenburner wrote:OK the best was is to use a deo can half cut of and filled with hot glue about half way. a piece of rubber on one end and one on the other (bumper and sealing face). simple. other wise use a pvs pipe with two end caps and O-rings or rubber as well

Before you can recommend a piston, what diameter is the piston housing?

A deo can will work for 2", but nothing else. Unless he's already told you what diameter it is through email because I don't see it in this topic.

Deodorant cans are alright as pistons, they may need to be replaced after awhile though.

Also, it might sound a little obvious but do check that your ball valve will allow the piston through, a 3/4" ball valve doesn't necessarily have a 3/4" opening.

It reminds me of one of my own projects in that the piston is held shut by mechanical means, not by pressure difference, though the latter does open it.

Another variation would be a take on this "valveless" design, where the ball valve would be between the projectile and the chamber, and the projectile would in effect be the "valve" holding the air as all the ball valve would be doing is preventing it from moving down the barrel.

MrCrowley wrote:

john bunsenburner wrote:OK the best was is to use a deo can half cut of and filled with hot glue about half way. a piece of rubber on one end and one on the other (bumper and sealing face). simple. other wise use a pvs pipe with two end caps and O-rings or rubber as well

Before you can recommend a piston, what diameter is the piston housing?

A deo can will work for 2", but nothing else. Unless he's already told you what diameter it is through email because I don't see it in this topic.

Deodorant cans are alright as pistons, they may need to be replaced after awhile though.

the diameter suppose to be 1/2" or 3/4".