1970 13-footer Hull Repairs

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
Aschubox
Posts: 3
Joined: Sat Feb 27, 2021 7:40 am

1970 13-footer Hull Repairs

Postby Aschubox » Tue Mar 23, 2021 1:40 pm

My 1970 SPORT 13 boat has been out of the water for about five years after a botched repair job on the hull failed and caused some de-lamination. Now the goal is to get the 13-footer on the water.

There is crazing all over the hull. Ant-fouling paint was hiding a lot of neglect. The photo below is typical of the hull.

I am plan to lay fiberglass mat over the majority of the hull especially, especially on the keels to repair damage and reinforce them.

After the mat is laid I will use fairing compound to smooth out the epoxy as needed.

Then using Total Protect as a primer before paint.

Should I grind out the crazing and fill before the fiberglass mat is applied?

Or, will the mat isolate the cracks enough?

Will 10-ounce [woven mat] form to the shape of the keels?

Will 10-ounce [woven mat] be too thick to form to the keels?

6A0EFF6D-8883-4065-98DE-4A4A22D318FD.jpeg
Fig. 1. No caption given
6A0EFF6D-8883-4065-98DE-4A4A22D318FD.jpeg (156.76 KiB) Viewed 1511 times


641594F8-2A4E-4475-A8B0-14F777A25AAA.jpeg
Fig. 2. No caption given
641594F8-2A4E-4475-A8B0-14F777A25AAA.jpeg (183.27 KiB) Viewed 1511 times

MartinDupre
Posts: 18
Joined: Thu Feb 18, 2021 8:39 pm

Re: 1970 13-footer Hull Repairs

Postby MartinDupre » Tue Mar 23, 2021 5:45 pm

Aschubox—My 13-footer hull had some crazing and some damage to the fiberglass at the chines and [runners]. In several places the foam was visible, but fortunately the previous owner had put some 3M5200 adhesive sealant in those places and I was able to verify no water absorption in the foam.

I did fiberglass repair on the obvious places: first, I cut out loose fiberglass material with a stripping wheel on an angle grinder; then I filled holes and gaps with West System Six10. Then I applied three layers woven mat using epoxy resin.

I sanded the crazed places level; then I used TotalBoat epoxy fairing compound on any gouges and on the worst crazing—which sounds easier than it was. I faired many times and sanded over and over using three different kinds of sanders and some hand sanding.

Primed with TotalBoat Total-Protect barrier coat (two coats). Then more fairing and sanding. The TotalProtect filled very, very minor imperfections but most of that work was done by the fairing compound.

Everything to this point was two-part epoxy. Finish coat was two coats Epifanes two-part polyurethane. I have spared no expense so far, as I plan to do this only once.