Making your own flapper valves

[ScoobieDoo]

A vintage diving dentist gave me some info on making your own flapper valves for pennies, if desired.

Obtain a commercial (or existing) flapper valve and make a plaster mold by pouring plaster of Paris into the flapper valve itself. Once the plaster cures and has hardened, you have a perfect 'mold' of the valve.

Next, obtain some commercial liquid silicone, rubber, or latex casting material. I am currently experimenting with various materials to obtain the best medium for making valves.

Take your plaster 'mold' of your flapper valve and dip it into the liquid material (or, paint it onto the plaster 'mold' with a paint brush). Allow to cure. Dip again or brush on additional coats of material to make to desired thickness.

This dentist tells me it makes beautiful
flapper valves and he hasn't had to purchase one in years!

Plus, this gives you something to work on on rainy days or days when you stuck in the house and can't dive!

[SeaRat]

Very interesting.

Thanks,

John

[ScoobieDoo]

I'm currently in the process of making several 'prototypes' to test various latex and rubber materials.

I'll give a full report when concluded.

Some of the things I will be testing is: Strength, durability, proper thickness, function-ability, resistance to sticking together, etc.

[sapperdale]

How did this project turn out?
Did it work as you had hoped?

[cstmwrks]

I'll give a hint on the sticking togeather part with anything molded of latex. It will need a chemical treatment or it will forever stick. Chlorox bleach at a 1 to 10 ratio with water and a 15 min soak will help. There are better ways but they involve truely leathel chemicals to produce a superior job.
Bill

[cstmwrks]

On the plaster mold subject and for what it is worth the correct term is "former" when dipping any type of compound. One does not need to make multiple dips with a plaster former to build up the thickness. Let the former set in the latex for 10 to 15 minutes. The plaster former absorbs water out and "gels" the latex on the surface of the former. As I recall 20 minutes made a build up of .018" thick ( cured that is ) on a guage boot I made this way.
I just do not see plaster holding up on the thin part of the duck bill valve.