by Mike - Alumilite » Mon Feb 27, 2012 7:58 pm
The resin should be completely cured, hard, and inert. It should not be tacky, wet, or soft in anyway. Couple more questions ... is it everywhere the material was sanded or do some areas cure without a problem? How soon after pouring are you sanding and painting? My only thoughts ... and I'm sure you've covered these however we are simply trying to get down to the bottom of the issue ... are that if its not everywhere but only certain areas, it could be a mix issue where the sides or some are part of the cup isn't mixed and we get a portion of the resin that gets scraped into the mold that doesn't crosslink fully ... there are still "x's" looking for some "o's" to crosslink with. The other is if the resin wasn't completely cured and crosslinked. Typically it doesn't take 72 hours but may take longer than overnight to fully crosslink, especially in thin or smaller lures.
I'm sure you've crossed these bridges but to make sure we are not missing something I bring them both up.
If neither of these are possibilities, run through your process for me ... % of microballoons, slush casting, back filling with foam, how and with what you are sanding with,type of paint, yada, yada, yada ... and let me try to reproduce your issue.
Mike