That does not come easily, only with sandpaper. But only wet sanding possible. Or using kilometers of sandpaper. It looks like good glossy surface. But when touching it with fingers and holding finger longer, it feels a little bit sticky. And that does not come out even after two weeks of keeping in warm. Only mechanical removal is possible. Also I've noticed that covering another layer of hotcoat causes week adhesion if  that sticky layer previously is not removed but for instance only made mat.
So what factors else I should consider ?

waxy surface? did that come off easily?  Sounds like a bit of amine blush which could be caused by a couple of factors.


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

The resin underneath is hard. It looks like it is covered by thin softer ( waxy ) layer. 

Strange that you have more issues. that batch last sold about 3 months ago so is less than 5 months old overall.  We haven't had any reports of issues yet so it is useful to work out what is going on.


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

I've ordered 1kg XCR yesterday. Will see how it behave. I have suspicion that only this particular batch could have problems. If that will prove, I would like to return one unopened 5ltr package. 

Hi Warren.
I'm worried about XCR resin behavior. I have put one layer of hotcoat on EL2 resin. It feels a little sticky even after 4 days of curing. This time temperature and moisture in workshop was controlled precisely between 21-22deg.C and 40-45% moisture. Anyway it's not possible to sand it dry. It clogs even 60 grit sandpaper immediately. See attached batch numbers of that XCR epoxy. Because XCR resin that I bought last year had much better properties. It dry sanded easily.
Here you'll find a link of short movie that explains it  :  https://we.tl/t-OYbCn5oCzj

Unfortunately there are too many factors and variables at play which can have an effect on how sensitive to moisture the resin ends up being in a set situation.  Hence no precise manufacturer data tends to exist.


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

I'm asking particularly about XCR resin. Anyway gonna hang higrometer in workshop. Probably I will report you more precise numbers .

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Thanks for immediate response . How would you recommend what point of humidity is advised not to pass to expect good hardening process ?