freedom 28/35 cat ketch rudder trim tabs or?

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VeloFellow
Posts: 129
Joined: Tue Dec 24, 2013 9:41 pm

freedom 28/35 cat ketch rudder trim tabs or?

Post by VeloFellow »

The barn door ruddder gives a lot of power in shallow water, but requires a lot of power especially when healed. Any one ever add a trim tab or do any other redesign to reduce input required?
Mike
s/v Clave'
1981Freedom 28 #112
Currently sailing Tampa Bay
Buit by Fairways Marine Hamble England
cat ketch, centerboard , wishbone booms, tides track slides
yanmar 2ym15 2blade prop

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hxschiller
Posts: 88
Joined: Sun Dec 07, 2008 7:55 pm
Location: Mull 28 - "Impulse" on NW Creek in New Bern, NC

Re: freedom 28/35 cat ketch rudder trim tabs or?

Post by hxschiller »

Please refer to Mr. Hoyt's more recent creation for a solution. The Alerion Express Cat 19 has a (relatively) high aspect rudder concealed inside the "barn-door" rudder which drops down like a centerboard. It lets you have your esthetics and your performance too. With a lot of effort such a rudder could be developed for the Freedom 28- (Mark 1)

peaceandfreedom
Posts: 258
Joined: Wed Jul 29, 2009 8:51 pm
Location: F33 CK & F38 CK Milford ct

Re: freedom 28/35 cat ketch rudder trim tabs or?

Post by peaceandfreedom »

Hello Mike,
I am also looking into a small trim tab to attach to the rudder of my F28 CK, to be operated by a wind vane or small tiller pilot. I came across the following article written by Paul Fay, http://www.faymarine.com/plansite/fay_m ... cht_pl.htm. I believe you will be able to gain considerable insight into the workings of a trim tab rudder from this article.
Happy sailing
Jim D

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Peter
Posts: 22
Joined: Wed Sep 16, 2009 4:12 am
Location: Bremen, Germany, UK F35 CB Cat Ketch 'Avante'

Re: freedom 28/35 cat ketch rudder trim tabs or?

Post by Peter »

I had a UK buildt F35 cat ketch 20 years ago. After crossing the Atlantic the PO had cut off at least 15% off of the rudders area from its trailing edge in order to make the loads on the helm lighter. As he was not content with the steering ability of his Autohelm 3000 wheel pilot, he added a trimtab to the rudder and let the motor of the Autohelm move the trim tab. He said it worked ok.

As I intended to sail the boat back from the Caribbean to Europe this construction seemed too fiddly to me and I installed a pendulum rudder Windpilot self steering device instead. On my way back I never suffered lack of steering ability caused by the reduced rudder area.

The weak spot in any trim tab construction is when going backwards. It is ok for long passages but when you have to manoeuver in tight quarters you either need to withdraw it or fix it to the rudder.

Cheers Peter

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

Re: freedom 28/35 cat ketch rudder trim tabs or?

Post by Castaway »

We have a Windpilot and an Autohelm 3000, too. The Autohelm is easily overpowered in a seaway, so we also have a Tillerpilot which attaches to the Windpilot instead of the vane, that holds in most weather. It's good for running straight downwind, (when the windvane is at its least effective), and motoring when there is a sea running. We keep the Autohelm for inshore work in winding channels.

We still have the full sized rudder. I had wondered about putting a small balancing area on the forward edge, but this is so close to the propeller that it might be uncontrollable under power. Anyone know?
Gerald Freshwater,
s/y 'Castaway', (UK F35 cat ketch, centreboard, 1987)
Lerwick Boating Club
Shetland Isles, Scotland

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