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Re: plugs and stuff - mold release
By:Hank
Date: 7/9/1999, 4:13 pm
In Response To: plugs and stuff (Berkeley C.)

A mold release can be made from vegetable oil and bar soap. It has been a while since I have made any - it keeps a long time and I am still using the last batch.

I have used this mold release on a variety of surfaces with good results. It is easily removed from any surface that can be washer with water.

This release can be used when making plaster copies of plaster patterns. It can be great fun molding animal tracks with the kids - keeps them busy for hours!

Basically, you want to melt the soap in a bit of hot water so that you can stir in the oil, then continue to heat the mixture until most of the water has been driven off. The mixture should be firm when set (it is more liquid when hot).

A potato peeler is handy to reduce the soap bar into shavings that would melt faster. Plain soap with out fancy additives and scents works best, I used those yellow bars of laundry soap. Add about a tablespoon of vegetable oil for each "bath size" bar of soap.

Store the stuff in a plastic tub with a good fitting lid. Label clearly (my margarine container full of mold release looks just like margarine!).

The mold release is used just like the old fashion shaving cream - with a soft brush. Work up a lather (right in the plastic tub) with a slightly wet brush. Apply a two thin coats to the mold allowing it to set between coats.

The foam dries to a smooth thin barrier. Porous surfaces (like plaster or cement) will need more than two coats to fill the pores. For multiple moldings, freshen the barrier as required. If you are molding some thing with fine details it is best to remove all the release and reapply between copies.

I have not tried this stuff with epoxy yet but I will be doing so with in the next couple of weeks when I cast my butt to make a pattern for a custom kayak seat.

Hope this is of interest.

Messages In This Thread

plugs and stuff
Berkeley C. -- 7/9/1999, 1:31 pm
Re: plugs and stuff
Paul G. Jacobson -- 7/10/1999, 11:49 pm
Re: plugs and stuff - mold release
Hank -- 7/9/1999, 4:13 pm
Re: plugs and stuff
Ross Leidy -- 7/9/1999, 1:52 pm