John_Madison CT wrote:Thanks [Phil]. I called a local marina with a very reputable fiberglass shop for a ballpark estimate to fix this, and they quoted $4,500!
So, if I end up with the boat, I'll be doing the repair myself.
$4500..... That's crazy since the materials and labor are not even close to that figure. Attack it yourself, it's not difficult.
Here is the process on my cavity cover, not a Whaler, but process is the same.
The inner skin came off easily and the core was badly rotted, so it was easy to remove with a scraper. Once the inner skin and core are removed the outer shell is not that strong, so make sure you support it.
Make any repairs to the outer skin while it is exposed. I filled in mounting holes from the previous owner (it was a Florida Marine Patrol Boat). Prep the surface with 24 grit to increase the surface energy of the bonds.
I then cut and fitted a plywood core. I chose to cut the core into pieces to reduce the possible warpage when laminating. The core is not where the strength is, it separates the inner and outer skins where the forces are carried.
I laid down glass and resin and set the core pieces in place and covered that with a release liner and lots of weight - batteries, paint cans, lead weights, anything that will maintain pressure so air is pressed from the outer skin and core.
After curing, I roughed up the exposed core and prepped for glass and added several layers of fiberglass in the layup process.
My cavity cover was stronger than when made, due to the extra layers of glass. Ready for primer and then Awlgrip.
While in there it's always a good idea to pull and inspect the tank. I was lucky and the tank was still in great shape, but some fail earlier than others due to salt water corrosion. I decided to pull my tank and paint with zinc chromate primer and followed that with bedliner.
Tank was installed and foamed into place. (top was not sprayed in bedliner since it's not in contact with foam. Whenever installing a tank, NEVER use rubber pads or strips since the carbon in the rubber can lead to early tank failure.
Foaming the tank in is quick and easy with 2 part foam. I poured into the contained, covered and shook vigorously for 30 seconds and then poured and it worked great. Warmer temps or shaking too long could cause the reaction to create excess pressure in the container, so be careful.
Tank installed, new hoses and grounding lines ready for more foam.
Some insist in using epoxy, but it's not necessary. The bond strength of polyester resin is plenty strong. The cost of epoxy is far more and the cure times excessive. With polyester you can do multiple layups in an afternoon, where epoxy can take 3X or more time with the concern of amine blush that must be washed off.
D-