Piston Valve Design

[Mr.Tallahassee]

I've been doing research while trying to figure out a new valve for my airguns. I thought about it and put a QDV design together with a regular pilot actuated piston valve design. How well might this work? I'm not certain if this is a QDV or a QEV.

[saefroch]

It's not a QDV. It is quite a bit like the piston I built for my Trident (link in my sig, if you're interested).

[Mr.Tallahassee]

I just realized I did not need a check valve on this design
This would still be an efficient valve though, right?

[Gun Freak]

The valve won't work. Assuming your piston is airtight because of the check valve, upon filling, your piston would just move back and the fill air would go out the barrel. If you want a check valve piston, you have to fill pilot. Other than that, it's just a normal piston valve, no resemblance to a qdv.

[Mr.Tallahassee]

I realized that after I posted it. It won't have a check valve in the real thing. Could I melt scrap HDPE for a piston? I'm on a very tight budget with this project.

[jackssmirkingrevenge]

Ditch the o-rings and the check valves and put a spring behind the piston and you'll be fine.

I'm on a very tight budget with this project.

Let binary adhesives into your life

[Mr.Tallahassee]

I would love to use epoxy but it's a bit expensive to use for making a 2'' pistons. I thought about using wood disks bolted together in the way shown in the pic. It's for my newest PVC gun http://www.spudfiles.com/forums/second- ... 23007.html

[Technician1002]

I realized that after I posted it. It won't have a check valve in the real thing. Could I melt scrap HDPE for a piston? I'm on a very tight budget with this project.

To save you the trouble, I was on a budget when I built a competition t shirt launcher. Melting milk jugs and such is a waste of time. Just before it it hot enough to burn, it becomes the consistancy of gummy bears. It forms into a solid mass much the same as a bowl of gummy bears.

I did use some sheets of HDPE and used heat and LOTS of pressure to clamp them together. This worked OK but it is more difficult than it is worth.
Photos and how to do this is on this page from the contest.

https://inteltrailblazerschallenge.wiki ... +brag+zone

[jackssmirkingrevenge]

I would love to use epoxy but it's a bit expensive to use for making a 2'' pistons

If the piston is built up as opposed to being cast as a solid block, you're not going to use much. Some cheap filler like sawdust will make it even more economical.

[Gun Freak]

Or you could make it cup shaped to decrease weight.