[BrianB]

Very cool info and it was exactly as I thought you said. One other question and I do do my clay beds exactly like you do yours. How do you figure out the volume of RTV to use so you don't pour so much or too little? I use 4 "L" shape pieces to surround my mold box instead of legos. It's just a little faster.

[Vodkaman]

BrianB, two methods.

#1, the box is rectangular, so the volume can be easily calculated by multiplying the length x width x height. You might want to subtract the lure volume, but I wouldn't bother, too deep is better than too shallow.

#2, More accurately, fill with water to the level you require. Pour the water into a container and weigh the water in grams. This will give you the volume in cm3, 1 gram of water = 1 centimeter cube. But now you have to dry the setup, as drops of water will probably leave pockets.

I use method #1 for RTV, method #2 for PoP.

[BrianB]

Vodkaman, Parden me It's been a while since I was in school. If I do L x W x H would that give me volume as in ounces of RTV to use??

Also, I understand the purpose of silicone. But why not substitute a thin vaneer wood say an 1/8 of an inch thick and drill holes in it so that you can bind it to the mold when you pour some RTV over the top of it and sandwich it? Seems easier/cheaper/time and more solid?

[Kajan]

You can figure out your cubic inchs and weigh your RTV. Figures I found were(specific volume) 24.7 cubic inchs/lb which would be 1.55 cubic inchs/ ounce(weight)

Correct me if I'm wrong, been long time since I was in school also LOL

[dramone]

sorry guys...havent been around a while.

1. rtv-silikone will cure faster when water ist added (durability and strenght of the mold decreasing). i use some drops of water for long curing rtv as an shortcut. if you use the "bombs away method" YouTube - How to make a simple Silicone Mold Part 2 shown at 4:08

so, no airpockets in the mold, even when water is added. the rtv will lose its viscosity "linear" to the amount of water added.


2. measure the amount of rtv needed with rice instead of water (lure allready in place). the volume of rice is pretty much the same as rtv. (volume vs weight).

thx Husky for all the hints

[captsully18]

Husky, method has been working great for me. By using this I can probably 2-2 1/2 molds out of same amt. of RTV that I at first only got 1 mold. I must thank you for this info.

David

[Vodkaman]

Dramone. re - post 15.

#1. Well I never knew that!

#2. excellent idea!

Thanks Dramone & Husky.

[Kajan]

Good to know Dramone, did'nt know y'all had rice in Switzerland LOL

[dramone]

how to "stretch" rtv with caulk for molds. (reuse of old molds also)
i made a short tutorial a while ago for a german site, based on Husky's hints (yes, i put his name on top of the tut, because it was not my idea and to give him the credit). ok, it's written in german, but the pic's will speak for their own . send me a pm if interestet.

EDIT:
oops...i'm not a club member, so no pm...sorry