Then a few days after demoulding, I trimmed the first tray up. After washing the dust off with soap and water, a sticky cloudiness began to appear in patches. Starting along the edges, it almost seems to spread over the part. Nothing I have tried can get it off, I've tried acetone, soap and warm water, I even sanded it back and then polished it up again, but it just doesn't come off. Strange thing is I can sort of smudge it around with my finger, and it even balls up as if it were a wax or something, but can't remove it.