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What is OOMOO 30 ?

It is a peculiar name and I bet there is a scientific basis for it but it is an easy to understand product.

This is liquid rubber for mold making. It comes in two parts. You mix the two parts together then pour it. And it creates a rubber mold once it cures. Pretty cool and really very easy to do.

I will show you how to use it and some of the projects I have used it for.



Smooth-On Silicone Mold Making Rubber OOMOO 30





Some of the Technical stuff: OOMOO 30 has a pot life of 30 minutes and a 6 hour cure time. And it has a moderately high temperature resistance which means you can actually cast some low melting point metals in it. I have done this with a bismuth alloy. You can check out that tutorial right here: Casting Metal Miniatures

Here are four molds made with OOMOO 30. This gives you a good idea of what you can do with i. I made molds so I could make copies of dwarves and treasure chests.

A group of cast miniatures



mix the rubber


You mix together equal amounts of the two parts of the oomoo.


Pour the rubber into the mold


Then pour it into your mold. In this case I am making a mold of a miniature dwarf so I can cast copies of the dwarf.

Remove the mold


Once the rubber vulcanizes and is cured you can remove it from your mold.

Inspect the mold halves


And now you have a rubber mold of your item. You can use it to make copies.


Remove the miniature


Here I have used the rubber mold to make a plastic dwarf. And I can repeat this process re using the mold many times.


I make seven dwarf copies. They are the white ones. The grey one is the master that I sculpted then molded.

The duplicate dwarves


The miniature dwarves are a complex item with a lot of detail and it requires a rubber mold that is in two halves. But you can make simpler objects with a one part mold. You cast the oomoo on the part and let it cure. You are done.

One Part Mold

This picture shows a one part rubber mold I made to make copies of treasure chests.



Smooth-On Molding and Casting Starter Kit with Oomoo 30 and Smooth-Cast 300



Faster Cure Time (OOMOO 25)

Smooth-On OOMOO 25 Trial Unit 2 Pint Kit - Tin cure Silicone

This is pretty much the same as OOMOO 30 except that it cures much faster. It has a 15 minute pot life and it cures in 75 minutes rather than six hours.




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