I removed two 6" dia speakers from the cockpit and need to patch the hole. The speakers were down in the footwell area on the vertical panels rising from the cockpit sole. I've already patched the holes from the inside, but now need to finish the exterior. I used polyester resin so it's compatible with gel coat.
What should I do to finish off the exterior of the holes? gelcoat? The surface is kinda rough; it's just bare polyester resin and mat. I need to fair it smooth and match it as closely to the surrounding gel cost as possible. I don't really want to paint yet. Can polyester resin be thickened like epoxy? If so, with what?
Thanks
First off there is a huge difference between patching the holes and finishing the holes. You are well on your way to patching the holes. You are correct, gel coat bonds well with polyester resin but does not with epoxy. Unfortunately epoxy is a much better repair agent for everything where polyester is not.
One of the peculiarities regarding gel coat is the thickness. The average thickness of gel coat is recommended to be around 20 mills or around 20 thousands of an inch. Apply gel coat too thick and it tends to crack. That being said they do make a gel coat that is thickened in gel form and I have applied it up to an 1/8" thick with out issues. Spectra makes gelled kits color matched. http://spectrumcolor.com/ (http://spectrumcolor.com/)
Here is where we are getting in the finishing portion of the discussion. Even if you find your color, the chances of it matching the decades old color on your boat are slim to none. Even if it matches today a year from now it will not. If you are picky about how it is going to look, you may want to consider painting the lower cockpit area designing the "breaks" between old and new at the most subtle areas.
Dale