"Alt molding material or not" Topic

Ive been considering do some molding and casting.

Found this, seems to me to be super close are almost exactly the same overall substance as people have youtube videos of starch and caulk.

For those that have used real molding and casting materials. What would be the problems with using something like described in the article?

link

I have seen that product before but never got round to trying it. In theory thare should be no problems. The things to think about would be as this is designed for encapsulating electronics and suchlike will it have the ability to hold fine detail needed for casting – thought the 2 inch cube is showing some fine lines from the case join. . Also resin casting can generate a fair amount of heat – will this material resist that.?
And how long will it last before it breaks down. Obviously a lot of this depends on what you intend to cast in it. Some simple walls or trenches will not be as destructive as something with undercuts which require the mould to be twisted and stretched to extract the cast.
I guess the best thing would be have a try and see what you get.
Tim

I have not made a corn starch and silicone putty, but I have made molds out of silicone caulk using two different methods-

1. squirting the caulk directly into a bucket of warm water with a little dish soap. this makes the silicone cure relatively evenly and quickly, as well as being significantly less sticky. I have a few molds I have cast plaster into several dozen times over five years or so. The detail is not as good as professional materials, but it works. Any putty type mold like this is proe to trapping air and making odd protrusions where edges of the putty meet but do not fully touch the form.

2. dissolving caulk with mineral spirits to make a brush on mold material. a few thin layers are built up and allowed to cure between layers. The form needs to be resistant to the mineral spirits. This is more toxic than method 1, but works well if you want a brush on mold material.