F33 CB attachment point faioure

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Erik
Posts: 35
Joined: Thu Dec 14, 2017 7:24 pm
Location: Stony Point, Hudson River New York USA

F33 CB attachment point faioure

Post by Erik »

Last week while winching my CB up the attachment point on the board failed. The lift line and safety line were both attached to the same point you can guess what happened. The board came crashing down with a loud thud. Thankfully after hauling the boat there seems to be no damage. It was a bxxxx making a temporary repair and getting the board back in the CB trunk. It appears the SS hook was welded to a plate imbedded in the CB. The failure occurred at the welds in 2 places. Has anyone out there suffered the same kind of failure and how was it repaired.

Thanks
Erik
I am going to try and attach a couple of photos

Erik
Posts: 35
Joined: Thu Dec 14, 2017 7:24 pm
Location: Stony Point, Hudson River New York USA

Re: F33 CB attachment point faioure

Post by Erik »

To All
I guess the pictures didn't attach here is the 2nd try
Attachments
Mariah CB (2).jpg
Mariah CB (2).jpg (2.67 MiB) Viewed 2569 times
Mariah CB.jpg
Mariah CB.jpg (3.23 MiB) Viewed 2569 times

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Castaway
Posts: 286
Joined: Sat Dec 13, 2008 8:40 pm
Location: Lerwick, Shetland Isles

Re: F33 CB attachment point faioure

Post by Castaway »

I've been frightened of this happening for the past twenty years! We have a 'safety line' attached to the stainless loop, supposedly for if the lifting pennant breaks, but it wouldn't have saved you. I attach a picture of the same fitting on Castaway, when I raised the CB into the saloon to replace the rubbing pads at the aft end of the CB. This is how it's meant to look, but I can only imagine that you will need to remove the board, cut it open, and build a new attachment point, which might well be better designed, preferably separating the pennant and stop line attachments, so they do not fail together.

If I was taking my centre board out again, I would cut it open and remove half the ballast, putting that into the bilge. It would make very little difference to the stability of this already stiff boat, and raising the board would be so much easier, I'd adjust it every time I changed the trim. A good many years ago, I hit a rock and split the lower end of the board, but wasn't around when the repair was done (in another country), so couldn't get that modification done, although the board was cut open and re-glassed. If you have the chance, give that option a thought.

Happy sailing, when she's fixed!

Centreboard pennant attachment
Centreboard pennant attachment
CB attachment 433.jpg (146.41 KiB) Viewed 2249 times
Gerald Freshwater,
s/y 'Castaway', (UK F35 cat ketch, centreboard, 1987)
Lerwick Boating Club
Shetland Isles, Scotland

Erik
Posts: 35
Joined: Thu Dec 14, 2017 7:24 pm
Location: Stony Point, Hudson River New York USA

Re: F33 CB attachment point faioure

Post by Erik »

Sorry it's taken so long to get back concerning my centerboard issue. I lifted the boat as high as possible to access the top of the CB. I used a 1 1/4" hole saw to drill thru the CB 1 1/2" below the top in the location of the original lifting point, but no through the fiberglass on the other side. Next a 1/2" hole was drilled from the top centered on the 1 1/4" hole previously drilled. One of those vibrating saw was used to flatten the top of the round hole drilled thru the CB. I used a 2 x 1/2" SS eye bolt with a heavy flat and lock washer bedded in Marinetrex then bolted in place to serve as the lift line attachment. Once the Marinetex has hardened the 1 1/4" hole was backfilled with a structural marine filler. Lastly before the filler had set up the fiberglass plug removed by the hole saw was pushed in place and faired. I also lag bolted a large pad eye to the back of the CB to serve as the safety line attachment point. The back of the CB is solid fiberglass so this repair/modification should outlast the boat. I hope this helps. I have taken some photos along the way and will try to attach them at a later date

.Regards Erik

1983 Freedom Cat Ketch
Mariah
Stony Point New York.
Attachments
IMG_20230511_121618772.jpg
IMG_20230511_121618772.jpg (957.09 KiB) Viewed 240 times
IMG_20230512_104549070_HDR.jpg
IMG_20230512_104549070_HDR.jpg (1.25 MiB) Viewed 240 times

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