Addition cure silicone rubber mould sticking

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Addition cure silicone rubber mould sticking

Author	Message
Ray Rogers	Ray Rogers posted 9 Years Ago HOT Topic Details
Group: Forum Members Posts: 18, Visits: 79	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?
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Warren (Staff)	Warren (Staff) posted 9 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 7.9K	With 20 pulls or so, the Mould itself may be wearing out and the surface may have become slightly damaged and hence the sticking. You can extend the life a little by using some pure silicone oil after each pull to restore any oils that dry out of the silicone. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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Ray Rogers	Ray Rogers posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 18, Visits: 79	Warren Thank you for the information, seems strange that say pull number 20 was ok and number 21 was impossible to remove from the mould. I wondered if there was a possible change in the mould over the months it stood, perhaps 'drying' or contamination from dust etc. Is silicone oil something you supply please? Regards
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Warren (Staff)	Warren (Staff) posted 9 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 7.9K	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. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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