Epoxy resin pistons

[qwert123]

I have been told that epoxy resin will make a better piston than hot glue. When I make the piston, how should I prevent it from sticking to the mold? The mold is PVC pipe. Thank you for the helpful input. 

[metalmeltr]

Make sure the pipe is clean and smooth on the inside(Do not sand)
Wax the inside of the pipe with this.

Just rub on with a rag and wipe off the excess. The piston should pop out with a firm tap from a dowl or hammer handle. I have done this several time with great success.

[jackssmirkingrevenge]

I've used automotive grease and even butter in the past, the important thing is that the surface is smooth and well smeared with something slippery. It should also be a perfect cylinder, one of the reasons why I favour casting in syringe tubes.

[metalmeltr]

The inside of pvc isnt always perfect so it may require a little gentle persuasion to remove the casting.

[Major Collins]

yep im with jacksmirkingrevenge here go with grease , i use car bearing grease works like a charm.

[qwert123]

Wow thanks! Just got a great piston from fiberglass resin.