Hi guys,
Been skinning for quite a while but now I've stumbled onto something new. I was doing a pair of doorsills using 400 gsm cloth. I applied the first coat letting it go to a full cure and then applied the 2nd coat ( epoxy laminating resin + fast type hardner) with sanding cause I felt the first layer may have been too thin.

2nd coat went for a full cure and then I started wetsanding it ( 400 grid ) After getting it all even, I saw white marks all over the panels, nothing new but this time they remain visible :-( Wiped it down with acetone but even then I can still see them .. Do I need to sand down even more or did something go wrong here ? Please advise :-)

Sounds to me like you got amine blush "trapped" under the second coat ... but since you let it cure fully and sanded the first coat, that sounds like the first coat did not in fact cure fully?

What kind of temperatures are you working in ? (This is a very humid winter!!, unless you are on the southern hemisphere .. )

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