I'm not sure what it is, but at least it was supposed to be vinylester: https://composite24.co.uk/gelcoats/vinylester-tooling-gelcoat

I don't know if it matters, but first I applied gelcoat to this mould too, but since I saw that how difficult the layup was I decided to remove it. I was very easy remove with fingers. Then I layed up the carbon fiber, without applying more relase agent before since what I understood, it isn't needed every time. I used this relase agent: https://www.jacomp.fi/wp-content/uploads/2017/12/marbocote-227-v6.pdf

Are you certain? I've only ever seen that green in a polyester.

That is definitely a release failure is why I'm asking.

No, it is vinylester.

Is that a polyester tooling gelcoat on the mould?

I'm maybe having a same problem. I haven't post cured the mould. I made the parts, used some spray adhesive in the mould and in the carbon to have it layed up better (no gelcoat). Now when I removed the part from the mould, there are something stuck in it. I don't know if it is the spray adhesive, or epoxy? I used Marbocoat mould sealer and release agent.

I post cured the part in the mould with infrared heater, about 3 hours in 60 degrees C. The other mould was ok, it didn't have the imprint marks. I applied gelcoat in to that mould first and cured in the same way. I didn't use spray adhesive with that.

Some a areas of the mould are clean and smooth. Same thing is in the part. I can clean the mould and the surface is then ok.What could be the problem?

   

Ok thanks warren, will take those points into consideration in future 👍
Was using a mix of slow and fast hardner, may have been a little green when I demoulded, Had been 18hours but prob only 18-20 degrees, will give it a bit longer next time.
Thanks

As well as postcuring being a factor, demoulding too soon can cause print.  Also if you demould too soon, the part is often harder to demould as epoxy will kind of grip the surface.  The epoxy can feel hard and ready to demould even if a little green still.  Especially if you are using the slow hardener, ensure you give it plenty of time to cure.  This can also happen if you do a high temperature cure or post cure and try to demould while the moulds are still a bit too warm. 

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Ok thanks 👍

These particular parts won’t be clear coated, which is a shame in a way, as I’m a painter by trade so that side of things is easy for me! hence why wanted to get them as good as then can be out of the mould , it was more the reworking the mould I want to avoided. Will get an oven sorted and post cure and go from there

Cheers

Yeah thats it.

BTW if you gonna sand/clear coat parts after it doesnt really makes much difference. Either way (post cure or without) parts will have some kind of  slight "print" trough (after post cure or later on).

So if you want mirror finish....... postcure, sand & clearcoat (if you want mirror mirror sand clear with 2k and polish).

Have fun infusing