Bow and Keel Gelcoat Repair

3430 has all the gelcoat worn off the lower bow where it turns down under the boat.  The section is about 2" wide and 16" long.  The fiberglass is glossy and shows no fiber.  I have sanded it all down with 600 wetsand emory paper, so it is smooth.  I think this is bad to have in the water.  (my boat sits in a wet slip), and should have Gelcoat added.   What do you think is the correct step?

You can sand it back with 120 to give it some grit, then botton paint it.  If the glass is solid - it'll be fine or, if it;s suspect looking,  you can clean the area with interlux 202.  Tape off area.  Re-sand with 120 or so, clean again with 201.  Buy a (2) part epoxy, like the West System, mix a small batch and paint it on with a throw away bristle brush.  Let it cure and lightly sand,  Bottom paint over it.
If it is a visible part that is not bottom painted - then you're into matching and mixing gelcoat - matching is the tough part - it really takes time and practice.  
Which sceanrio is yours ?

James Titus's picture

Great idea about 120 to give the surface some texture.  I would like to take a stab at Gelcoat.  I have done some other yellow Gelcoat fixes above the waterline,and besides a slightly different color down there will not be noticed.  I am guessing that since I will work inverted that it needs to be sprayed?  I have not done that before.  I have various kits and cans of Gelgoat from West. What products would you recommend, proceedures.  May as well learn to do it as well as can be done the best way.

I have never sprayed gelcoat but have sprayed a lot of awlgrip etc.  I'm not sure oif the little disposal spray bottle they sell at West Marine will shoot geklcoat look into that...  I have brushed gelcoat on and that is what I recommend.
Matching and Fairing gelcoat   - I would get on youtube - find a vid on matching gelcoat ( there's a really good one with a guy who has a multi series on various fiberglass repairs - he has a pony tail.  He is thorough with his explanantions - although he makes it look easier than it is ).  Here -->
Personally, I would match gelcoat, prep area by degreasing - dewaxing with Interlux 202.  Then sand, clean again.  Gelcoat is pretty thick, but if it needs to be thicker to fight gravity, add some cabosil before you try to match color to thicken it.  Once color is close - add hardener, and brush on ( check vid on YT - again he shows how to get it on right ).  then let cure and fair.
I use gelcoat that has no wax in it in case I want to do mutli layers without sanding between - when I'm ready for final sanding, I spray with a chemical in a water bottle that allows it to harden.  But,  I recommend that you get it with wax/parafin - this way it'll cure and be ready for sanding once cured.
Check that vid out - it'll give you some great info...