I’m building a Chesapeake 14 with my son and we’ve recently completed the fibreglassing and epoxy of the hull. The 4th thin coat has started peeling though, with a few big sheets that come off easily in a few patches, like picking badly sunburned skin.

I’ve tried to attach a picture. I've asked elsewhere, who suggested it was due to me waiting too long between coats. I had waited probably a week before applying the 4th coat, so it didn't bond correctly.

Also, the garage I did it in is usually quite cold, but when doing the epoxy we had it heated to above 15 for at least 10 hours or so.

I have now started sanding it with 80-grit to remove any bits that I can that might seem remotely loose. It is making the epoxy look white and waxy, but that seems to go away when I wipe it down with a wet cloth.

Is this the correct thing to do? Sand it all down to 80-grit, and then epoxy over the top with a fresh coat? Will the epoxy be able to hold on to that texture?

Thanks!