A New Girl In the Works

[Rasper]

is the brown coating on the girl silicone

It's polyurethane. I use Reo Flex, made by Smooth-On. It's about half the price of silicone. Other than the powerful fumes, and the fact that it sticks to everything and needs a release agent, I find it just as good as silicone for my purposes. I use silicone for small intricate things.

Richard

[mite5255]

is the brown coating on the girl silicone

It's polyurethane. I use Reo Flex, made by Smooth-On. It's about half the price of silicone. Other than the powerful fumes, and the fact that it sticks to everything and needs a release agent, I find it just as good as silicone for my purposes. I use silicone for small intricate things.

Richard

Hi Richard, is the Reo Flex durable enough to get repeat wax castings, I'm also assuming it is not affected by uv rays. I have some resin Buddha's and some other small statues that I would like to copy in bronze or aluminum using lost wax.

I have done a fail amount of mold making in the past but using latex rubber for making garden ornaments in concrete

[Rasper]

Reo Flex RTV (Room Temperature Vulcanizing ) polyurethane rubber is unbelievably tough stuff. Should be good for at ;east a hundred wax castings.

Richard

[mite5255]

I'll give it a go

[Rasper]

What I have been doing is this:

I can only get the reo Flex 30 and the Reo Flex 50 in Mexico City. I have been buying the 30. The 30 is too runny for brushing on, so I thicken it a little with Cab-O-Sil for the first coat, and even more for the next coats.

I plan to try the 50 for the thicker coats. Using only the 30 works, but I would like the later coats to be more like a paste.

Also Smooth-On makes a polyurethane called "Brush-On" which I used once. It is thick and eliminates the sagging off problem, but to use it as a first and second coat on oil based clay is a little dangerous to the clay as I needed to press on the brush to fill in the details. Maybe two coats of thickened 30 and then "Brush-On" for the rest of the build up would be a good way to go.

Smooth-On has a distributor in Oz:

Rowe Trading
4 Holder Ave.
Richmond
South Australia 5033
Tel: 61-8-8234-0000
Fax: 61-8-8234-2092
fwoods@rowetrading.com.au sales@rowetrading.com.au
http://www.rowetrading.com.au/

Richard

[mite5255]

Thanks for that Richard , I'll get in contact with them next week. I'm also assuming the higher the number the thicker it is?

[Rasper]

I'm also assuming the higher the number the thicker it is?

I think so. I haven't run a test. The number is a measure of the hardness of the cured rubber on the Shore scale, hence the flexibility of the cured mold.

To thicken the rubber for brushing on I use Cab-O-Sil which is fumed silica and which Smooth-On sells as Ure-Fil 9. They also sell Ure-Fil 11, which they say is good for thickening Reo-Flex for brush on applications.

Richard

[Rasper]

The New Girl has a mother mold.

[mite5255]

Looks great Richard . what you call the mother mold, I have always called it the mold keeper, anyway that's how my father always referred to it while teaching me molding with latex rubber.

[F.C.]

What are those protrusions through the plaster for?