Talk Composites - The Forum for Advanced Composites

Addition cure silicone rubber mould sticking

http://www.talkcomposites.com/Topic19056.aspx

By Ray Rogers - 8/18/2015 7:50:11 PM

Hi!
Over the winter months I used an addition cure silicone mould 20 times or so to pour tinted water clear polyurethane casting resin into with good success. Last night I used the same material again but tonight the casting was really, really stuck in the mould to the extent I damaged the mould whilst trying to de-mould.
Any suggestions as to what went wrong and what I can do to prevent this again please?
By Warren (Staff) - 8/20/2015 9:16:05 AM

It could be a combination of those factors, a bit of dirt or contamination, general wear and the mould just getting to that point where it sticks.  When they start to go, the breakdown can be quite rapid.

We do not have any silicone oil but you should be able to find it in any decent hardware store.