F33 Center Board knocking

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Goose13
Posts: 77
Joined: Tue Aug 19, 2014 7:18 pm

F33 Center Board knocking

Post by Goose13 »

For the last week I've been Beating my Ketch up the coast of California and when I have the centerboard down going up wind I get a lot of knocking noise in the trunk from the board shifting around. Since I'm new to the boat is this noise considered normal? Its really annoying sound when your trying to get some sleep off shift.
Doug and Marie
Millennnium Falcon F33 CK cb #4
1980 wish bone booms Electric Drive

bad
Posts: 184
Joined: Sat Jul 09, 2011 11:14 am

Re: F33 Center Board knocking

Post by bad »

Did you buy the baby blue one that was for sale in down south last year?

When we had our F40 CC surveyed, the surveyor and I lifted the center board with a plank to unweight it off the pin it pivots on, then wiggled it side to side to get a senses of the amount of play. He thought it was fine, I have no idea :). Doesn't make a lot of sound while sailing. I did see remnants off some shims at the bottom of the trunk during our last haulout from the po.

You could try putting on some tension on the lifting wire and or change the position of the board to see if it changes things for the better.

At some point I would like to inspect the pin and bushing on our boat.... looks like a project though.

Erik

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1980raven
Posts: 101
Joined: Mon Feb 15, 2010 8:50 pm
Location: Warwick Cove, Rhode Island

Re: F33 Center Board knocking

Post by 1980raven »

My F28 CKCB makes noise when sailing in waves above 6' otherwise its pretty quiet. I have not tried to sleep underway so I can't comment in if it is sleep disturbing. Wish I was beating up the Cali coast. That would sure be better than being frozen in the cove here in Rhode Island.
Freedom 28 CK Hull# 14, centerboard, wrap around sails with WB booms
Narragansett Bay, RI

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

Re: F33 Center Board knocking

Post by Castaway »

Our centreboard has been banging about in a seaway for the 12 years we have owned Castaway; initially very frightening, but nothing has gone wrong as a result. About 5 years ago, we replaced the bearing at the pivot with a new nylon sleeve and stainless steel pin, which made no noticeable difference. This spring, if retirement, weather and yard allow, I shall replace the two mushroom shaped pads at the aft end of the board with thicker versions, so that the board does not have so much lateral movement when lowered.

I have no information at all as to how thick they should be, or whether the movement is normal. Some years ago, mentioning this on the Board, Michel (Tumlare, Alabama Queen) replied that he had no such problem. Our boat is fairly high mileage, it had done around 80,000 miles when we bought her, with several Atlantic Ocean races to her credit, so there may be a high degree of wear. It would be nice not to have the banging, but I don't want to find the board jammed down, so there will need to be some delicate adjustment of the strop which limits travel. How far should the centreboard swing down? When lowered whilst being craned out for antifouling, I have found it to come as low as to expose part of the upper surface at the aft end, and I thought it ought only to lower until it fills the slot in the base of the casing. I have attached a photo; comments from other owners would be welcome.
centreboard lowered to fullest extent of limiting strop; is this too low?
centreboard lowered to fullest extent of limiting strop; is this too low?
CB down.jpg (89.28 KiB) Viewed 8855 times
Gerald Freshwater,
s/y 'Castaway', (UK F35 cat ketch, centreboard, 1987)
Lerwick Boating Club
Shetland Isles, Scotland

bad
Posts: 184
Joined: Sat Jul 09, 2011 11:14 am

Re: F33 Center Board knocking

Post by bad »

if the hole in the aft edge of your board is for the lifting line I'm thinking the board is too low. This would mean you either want a top in the front so you can unload the line, or you need to limit the length of the line. Here are some images I've found that show other 33s with the centerboard.

http://www.mepsnbarry.com/category/jour ... wrong-way/
http://sailboatdata.com/viewrecord.asp?class_id=2996

Erik

Goose13
Posts: 77
Joined: Tue Aug 19, 2014 7:18 pm

Re: F33 Center Board knocking

Post by Goose13 »

Yes, I bought the little blue one in Oxnard, site unseen, so far I'm very happy with her, stable as a rock in wind up to 25. The only problems I've had is the engine, which is the original Yanmar 35 years old (I might through it overboard when no one is looking). Thanks for all the feed back on the knocking, I figured it was normal and I'm able to sleep through it now on a passage. I'll be in the Bay Area tomorrow for a few weeks if anyone wants to meet up.
Doug and Marie
Millennnium Falcon F33 CK cb #4
1980 wish bone booms Electric Drive

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gamayun
Posts: 270
Joined: Thu Dec 06, 2012 9:14 pm

Re: F33 Center Board knocking

Post by gamayun »

If you need a great Yanmar tech, there's one in Sausalito at List Marine that I can highly recommend and I have found to be quick workers. Let me know when you get to the bay. I am at Treasure Island. The weather is fantastic right now.

Carliane
s/v Kynntana
Kynntana, Freedom 38

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

Re: F33 Center Board knocking

Post by Castaway »

Erik,

Thanks very much for those links; I have seen the drawings shown in the second, but the photos in the first were helpful. Of course, Castaway was moulded and built in the UK, and there were two, slightly different centreboard shapes used here ( a friend keeps an earlier model in the marina here ). His looks the same as the photo and drawing, ours seems to be a little larger. The PO closely supervised the building, but I don't think he can have influenced the centreboard manufacture, which was made in the Isle of Man.

The hole you can see would probably be a good place to fasten a lifting strop when installing the board. I don't know if it was meant to take a line limiting the fall of the board when in use. There would not be much clearance if so, when the board is down. We have a line from the top of the GRP fork which holds the pivot, running to the attachment for the lifting tackle aft on the top of the board itself. This may have been lengthened to allow the board to be lowered further in an attempt to improve lateral resistance and thus windward performance.

If I can replace the 'mushroom pads', I shall review the attachment and length of the limiting line, mostly to avoid the board jamming in the 'down' position. This happened once, when a substitute block in the casing failed, and coastal cruising amongst the Finnish islands became embarrassingly difficult. The repair was not easy, either, as we had guests staying on board!

I'll post pictures of the work in due course.

Gerald
Gerald Freshwater,
s/y 'Castaway', (UK F35 cat ketch, centreboard, 1987)
Lerwick Boating Club
Shetland Isles, Scotland

bad
Posts: 184
Joined: Sat Jul 09, 2011 11:14 am

Re: F33 Center Board knocking

Post by bad »

GOOSE - Let us know where in SF you end up.

Kynntana - pretty sure we saw you last Sunday motoring from TI to the Berkeley Circle. You passed us shortly after TI. We had spent another lovely night on the hook at Clipper Cove.

Erik

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gamayun
Posts: 270
Joined: Thu Dec 06, 2012 9:14 pm

Re: F33 Center Board knocking

Post by gamayun »

I remember! What a good looking boat. Hope you had a nice time in Clipper Cove. It's a great spot. If I recall correctly, you went right through an area that should have grounded a normal-keeled boat. That centerboard is good to have :-) Are you based in Berkeley or just passing through, too?
Kynntana, Freedom 38

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