91% rubbing alcohol + petroleum jelly + plastic/silicone molds= problem?

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nsmar4211

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Wondering if anyone has any experience spraying the melt and pour molds with 91% rubbing alcohol to prevent ash after already using petroleum jelly as a release agent? Does it react with either the plastic or the vaseline? And does the 91% alcohol harm silicone rubber molds?

I bought a few MP molds yesterday to play with. Made a small batch of 100% CO because of how hard it gets and am very happy with the results! No warping or anything of the plastic molds, details are there, cute soaps. Also, my two new silicone molds needed no release and come out very cute. However, I am getting ash and since I want to give these as Christmas gifts I'm debating on how to prevent it. Thinking I may need to leave the soaps in the molds longer to stop it from forming on the "formed" sides (if that will even work)? They were ready to umold in 2 hours (literally). I might just say ferget it and wash the bottoms, but the "formed" areas will lose details if I do that.....

Any ideas?
 

lsg

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I have sprayed alcohol to prevent bubbles in M&P soap using the M&P molds with no problem. My experience is that CP soap usually releases from plastic M&P molds the first time they are used. From then on the CP sticks in these molds. You can grease them up with petroleum jelly, which helps and stick the soap in the freezer a few hours before unmolding. Let the molds set out for about 5-10 min. after removing from the freezer. This lessens the chance of the mold being brittle from the cold. Usually CP soap releases easily from silicone molds. Again, you can use the freezer trick, if sticking is a problem.
 

nsmar4211

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Ok, good to know, thank you much guys!
I greased from the get go because I've used the MP molds for plaster thingies and remembered how badly they got stuck :).

Just did another batch (yeesh this is addictive), it accelerated on me like mad so I glopped it into the molds and then dropped em a few inches to settle .... sprayed the tops with 91% alcohol until shiny. Will update to see if it helps...didn't spray the molds themselves before pouring. Thinking I'll spray half the bars immediatly after unmolding and see if it helps.
 

Obsidian

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I would leave the soap in the molds longer. If the detail side of the soap isn't exposed to air until well after saponification is complete, ash won't form.
 

dillsandwitch

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The only time high % alcohol reacts with plastic is ifbits stored in it for too long. It leaches out some of the nasties from the plastic into the alcohol. One if the reasons moonshiners keep thier brew in glass is to prevent any contamination. Spraying minuscule amounts on plastic isnt going to hurt it. I use my 96% forshots on my soap but I find it doesnt really do much. Covering with cling wrap has been working foe me lately
 
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