problem with two hot coats

General Discussion
1

hello, i glassed a 5’8 shortboard and when i put the first hot coat on it was very thin, so i decided to put on a second hot coat over the first one so that it would be stronger, i used sanding resin on both hot coats. when i sanded it afterwards, i sanded through the second hot coat in certain spots, now when i sand near the spots that are sanded through to the first hot coat layer it starts cracking around the spots and the second layer keeps cracking more and more. it seems as if the two layers didnt bond to eachother. now i have a sanded board with certain spots that are cracking and chipping off (only the top hot coat layer) and certain spots that are fine. what do i do? if i put more resin over the spots that are cracking, it will do the same thing when i go to sand it. any advice?

thanks

2

Did you forget to sand after the initial hotcoat?

Can’t add resin to an existing hot without sanding.

If you sanded, and it separates, I’d sand the whole thing down and re-hot, or just gloss it.

Don’t depend on hot to add strength, depend on it to fill voids so you can sand to flush.

3

no i didnt sand the first hot coat, i didnt know i had to, if i add another hot coat or gloss coat over it (everything is sanded now) will that fix the problem? is that the best thing to do?

4

yup…