Polyrethane foam pipe insulation as soap mould?

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Apr 22, 2015
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Hello all! I bought 2 meters of polyrethane foam pipe insulation and thought I would try to use it as a circular mold for soap embeds. Someone mentioned it might have chemicals that may leak into the CP soap. What do you all think? It look pretty perfect to me. Slit along the side, easy to tape together and cheap enough to use once if I have to break it to get the soap out. Will not make lots of it, so will not produce masses of garbage.
You mean something like this?

Ive used pvc pipe as a mold, but never the insulation - isnt that only an inch or two on the interior diameter? And is the inside perfectly smooth?
I'm actually not sure if this is a good idea, or a terrible one. Provided that the inside is perfectly smooth, how would you seal the bottom? Would taping the length be enough to prevent leaks?
If that pic is what you are planning on, I would think its a terrible idea. Its soft and foamy, almost like a sponge. I could see the soap sticking, leaking and possibly having some kind of weird reaction from the lye.
You can use hard plastic PVC pipe for CP or buy circular embed molds from soaping companies.
It will stick and could melt. You would have to line it with a silicone sheet. I use a 20mm pvc pipe for embeds and line it with a silicone sheet and have no trouble sliding it out.