PVC question in reguard to an airsoft mine design

[bobgengeskahn]

hello everyone, its been a while since I have posted but I have been poking in from time to time, especially since i started this mine project. so here is the question: is there a special way to resize the PVC to fit inside of eachother close enough to be used as a piston? I know that people have done it on a regular basis here, but when I try to fit parts inside of eachother at my hardware store they are just fractions of an inch too big or way too small. typically i am looking at sch 40 parts, could this be the problem?

The valve within the mine is currently based off of technicians t-shirt cannon with a sliding QDV. however i am debating going to some kind of a sealing face to avoid having to build such a small piston. (the inner tube is 1/2" sch40 pvc)

[SP00K]

With somethine that small it should be really easy to just cast one yourself out of epoxy. Although I have no experience there

[bobgengeskahn]

do you need to fit o-rings to epoxy pistons? ive never made one before...

[clemsonguy1125]

With a QDV piston yes, its possible to have a perfect seal with out but difficult, for a barrel sealing valve no.

[bobgengeskahn]

Ive been debating changing the design to a barrel sealing piston... ill try to post a paint drawing tonight when i get home...

[clemsonguy1125]

If its for a mine, you could probably use a sprinkler valve, but a barrel sealer will be easier to make work than a QDV

[bobgengeskahn]

i thought about a sprinkler valve origionally, but size is my main issue and i couldnt think of a way to conveniently ise one...

[Technician1002]

My Mouse Musket used 1 inch pipe caps that were simply sanded down to fit inside 1.5 inch pipe. The pipe was sanded out on the inside to make it slightly larger and perfectly smooth. The inside of the pipe was slightly bumpy before sanding.

1 inch pipe cap made the piston in the Mouse Musket.

[jhalek90]

This was made with sandpaper, a knife, a hacksaw, and a drill.
it is a paint ball mine powered by a 12g Co2 cart.
I am sure you can adapt this for use with airsoft.