Capri 16.5 Hull Crack Repair Questions

[truSailor7]

I live very high on the top of a mountain. We get LOTS of snow here and the snow has damaged my Capri 16.5 sailboat hull. (I move LOTS of snow but fell behind on a winter about 10 years ago... and the snow weight pushed the hull down onto the trailer and the hull cracked).

The wife has been nagging and threatening to get rid of my boat, etc. I want to keep the boat and repair the crack so I can sail her again.

Because of my remote location... there will be no professional fiberglass repair done. I will do it myself. I'm trying to develop my strategies for doing this but I have questions about the construction of the boat.

sailboat_damage_04_labeled.jpg (211.36 KiB) Viewed 14 times

The crack is about 12-14" long and runs from fore to aft. The shape of the cracked zone is basically still the same hull shape it was.

My first question is: What is inside the hull of this boat? Is it hollow? Is it filled with foam?

If it is hollow... my strategy is to cut a hole in the cockpit area for access to the internal zone and reinforce the inside with fiberglass. Then clean up and apply gel-coat or whatever to the exterior crack. Then plug the cockpit hole with the appropriate sealed panel.

If it is filled with foam... the structure might still be OK and I could just work on the exterior of the crack.

Thanks for any ideas!

[GreenLake]

The key is that you report the shape to be unaffected. You want to support the hull in a way that prevents this area from distortion.

I would start by grinding a wide bevel in the hull where the crack is. The usual ratio suggested for this is 12 to 1.

The exposed fiberglass should be dark. If it is milky, that's a sign of damage and more grinding will be needed.

Most likely you will end up with a bit of a gap where the crack was. That should allow you to look inside and assess without cutting any holes.

If foam, you can just glass from the outside. The foam will support the new laminate, so it doesn't sag into the crack. Maybe you need to shim with some foam if the grinding dug out a bit.

If hollow, you'll need a bit of backing for your repair. You can laminate something thin and flexible and shove it through the crack and glue it to the back side.nperhaps in sections. You can use sheet metal screws through the hull to pull it flat while gluing. Or use a wire to pull against a short piece of wood bridging the gap on the outside. The key is to help it bring the hull into local alignment and hold the backing flat while the glue cures. (Thickened laminating epoxy or ready made epoxy glue like GelMagic)

Once the backing is fixed, remove the screws or wire and laminate your repair. Don't wait too long and you can laminate directly onto your backing piece without sanding. System Three gives 72 hours for their Silvertip.

There are plenty of instructions out there on how to laminate over a gap with successively smaller patches of glass. Your repair should end up matching the original strength of the hull.

Here's a link to a similar repair. That repair was more challenging due to the nature of the impact damage, but in a pinch could have been repaired eorking from the outside alone.

There are other posts here with details on how to laminate. Spend a bit of time reading these archives and whatever you do, make a test piece of flat laminate on your work bench to dial in the process. Be super accurate and thorough in mixing your epoxy and the rest should come together.