Resin fusing to silicone molds

[IsoCaps]

I've been casting for a couple of years now and finally settled on materials that work for me.  However the last couple of molds I made have been fusing with the resin after only a couple of casts.  Tiny bits of silicone seem to bond with the plastic and I end up with small holes/defects in the molds.  This never used to happen, and I'm using the same types of silicone and resin as usual, and haven't changed anything about my process as far as I know.

Does anybody know what the chief causes of this kind of bonding are?  i.e. temperature, de-mold time, wrong silicone/hardner ratios, etc?  There's nothing more annoying (and expensive) than losing a perfect mold and I'm struggling to figure out what's suddenly going wrong.

[IsoCaps]

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[ilemondrop]

I have literally 0 knowledge of this space, but I just watched a few videos on it yesterday and every tutorial mentioned you need to spray a chemical onto the mold prior to injecting the resin into it to prevent sticking. If you're already doing that then

[IsoCaps]

Thanks- I do have some mold release spray and should probably start using it more, just curious beacause I must have cast about 100 caps sucessfully without it.  Maybe my luck just ran out

[yuppie]

Yeah, just use release. Maybe use a little more. Maybe try a different kind.

[IsoCaps]

Sure, will do.  I find using it results in more bubbles but I guess a failed cast is better than a failed mold 

[Findecanor]

Isn't that just the silicone mould breaking apart from wear?