Fiberglass filler/fairing

Hello everyone, New to this forum and seems to be addictive.

I have removed the center console of my 18' Whaler to cover up all the holles that over the years have been jigsaw cut for electronics etc.
The console is 3/4 inch ply covered in fiber, gelcoat etc... made in a mold.
I bought a sheet of 3/4" preasure treated ply and cut out the shapes od the holes to cover.
Inserted these (about 5 panels) in the holes to be covered, fitting them with preasure leaving them about 1/16 under the outside surface of the face/gelcoat/fiberglass.
Applied two layers of fiberglass mat on the inside to bond these repairs to the sorounding console fiberglass layup.

Now on the outside I have grinded away the 1/16 steps left by leaving the panels 1/16 under the surface and providing a better fairing surface and transition.
I have to fair the surface with filler but I am only familiar with cotton fibers and talc that I have used with polyester and epoxy resins in past projects.
Is there a better alternative to cotton fiber added to resins for this type of fairing? Maybe silica, micro balloons?

This is not a structural repair, and the structural part of it has been done with the fiberglass mats on the inside. For the same reason I am using the cheaper polyester resin instead of epoxy.
Eventualy I will prime and two part polyurethane coat, and re drill/cut for new instruments.

I am not to fond of Bondo body filler as it chips and breaks etc. (I have used the fiber reinforsed fiberglass filler by Everlast with good structural results but how will it sand for a smooth finish? And then take primer?

Alex Higuera

 

I would NOT use bondo but instead mix some microballoons into the same kind of resin that you used to patch the holes, sanding is pretty easy and after a little paint your boat looks as good as new.