Hi

need to build up the side of gunale with 3/4" gurit board/ VE laminate to the original Gelcoat on gunale. The laminate will be 3 strips of 4"x45" long
1. Do I roughen the gelcoat surface with #40 grit in preparation for the bond
2. grind all the gelcoat off, to get superior bond
3. use a epoxy bond instead of the VE

need some help on someone who is actually done this, as only need to do this once
merry christmas

I'm no expert , Youll have to ask Glass Dave !
But I would grind down through the Gel if you want a good bond . The VE will be fine.
I'm in the process of extending a hatch that has been painted 4 times .. and hacked all to hell.

dunnitagain

yes seems the most time consuming part is always the best way in the long term
starting grinding off the gelcoat today with #40 grit

drilled some holes into the gunale
will use one layer of 1oz CSM and 17oz Biaxle cloth laid on top of gunale first
then VE/West 413 filler as glue to bond gurit 1/2" board which has laminate 1oz csm /17oz biaxle on either side
2 layers of 1oz CSM/17oz
then finish off

Looks Good ! I would get all the white off though , that grinding can be a PITA.
You could us a DA with 40 grit to finish grind .