Small crack in sail boat hull, no access from inside.?

Question

I have a small (4 - 6 ") crack in the bottom of a 16' sail boat. I can not access the crack from the inside and am curious how I should repair from the out side. I' rather not add mat to the out side of the hull. Thanks

Answer 1

Spray Fiberglass  Resin for Boats.

http://www.fiberglasssite.com/servlet/St...

Answer 2

Sounds like a job for marine-tex (2-part fiberglass putty).

Great stuff, no need to layer it up - it'll cure in as thick a layer as you need then it can be sanded down.  But if you'll wet a finger and smooth it out before it cures, you probably won't need to sand it.  Bonds with fiberglass, wood, gelcoat.  The keel of my old boat is just about all marine-tex now, after a couple fights with the trailer.

This is the stuff

http://www.marinetex.com/PRODUCT%20PAGE_...

BTW I'm not affiliated with this product, just a real big fan.

Now - if I misread, and the hull is actually breached, you've got some fiberglass work to do - 45 cal gives a pretty good description of how it's done.  Another good resource is the restoration forum over on http://forums.iboats.com - guys over there that can walk ya through it step by step.

Answer 3

There is no such saying as a small crack below the water line??? If there is a crack? What caused it> If near the keel than you need to grind it out to see what damage water intrusion caused>Then you have to wash with fresh water> Then dry out> Fiberglass mat small pieces first then larger till filling in then grind  area> Grind smooth> Fill with marine filler sand smooth> Gelcoat to match or bottom paint>