[frers-list]Fairing keel and rudder
Courtney Thomas
frers-list@lists.frers33.com
Tue, 10 Dec 2013 09:25:19 -0500
Art,
Thanks for the data.
My understanding is that on the Frers33 a wing keel was an option whose
draft apparently was 4' 11". Is that from the keel root, waterline, or
what ?
The keel depth on my boat, measured from the root front to the foot
bottom, ... is about 40".
I don't know if a former owner modified said keel, or if I have a
"wing", though the foot shape is torpedo like and does not have a
horizontal wing.
More importantly, I'm concerned that someone, not a marine architect,
has sufficiently altered this keel so that it's ballast is insufficient,
the boat's handling is impaired if not dangerous, or that it's
performance is significantly reduced.
Please bear in mind my intended use is coastal cruising, not racing.
1-What's your opinion on my boat's circumstance ?
2-If of serious consequence, what's your recommendation regarding proper
assessment and remedy ?
Hopefully I'm unnecessarily concerned :-) but with a 50' mast and
sail capacity on such a small and light boat and it's intended 'below
the belt' ballast I'm concerned.
Most appreciatively,
Courtney
PS - Anyone else that will weigh in is welcome, of course.
On 12/9/2013 10:36 PM, ARTHUR KELLEY wrote:
> Here's where we are so far. We have information from 3 boats. It
> would be useful to get more.
> Boat A Boat B
> Boat C
>
> Rudder Length 60.5” 60” 60”
>
> Rudder Width from skeg 28.5” 26” 28.5”
> parallel to top of rudder
> Rudder edge 3/16” ~1/2" 1/8"
>
> Keel depth 54.5” 55”
> 55.5”
>
> Keel Root 68.5” 68.5”
> 69”
>
> Keel Foot not measured 28”
>
> Keel edge 3/16” 1/8”
> 1/8”
>
>
> It appears that all three of these boats have nearly identically sized
> keels although it would be interesting to see if the curvature of the
> trailing edge matches. We should probably at least get a measurement
> horizontally at a station halfway between the root and the foot. It's
> still difficult to tell in a second round of photos. The difference
> between the keel depths is probably not important, and probably not
> intentional. Boat A has relatively soft fairing compound on the
> bottom of the keel which appears to have been crushed when set aground
> for the winter.
>
>
> On these three boats, it appears two have had their rudder trailing
> edges "faired" to a finer than original edge by adding an extension of
> approximately 2.5".
>
> I will continue to gather measurements from whomever is willing to
> provide them so we can see how close the boats' foils still are. With
> owner's permissions perhaps we can then disclose which boat is which
> and postulate whether any of this really makes a difference.
>
>
> Art
>
>
> On Mon, Dec 09, 2013 at 11:13 AM, Courtney Thomas wrote:
>
>> On 12/7/2013 4:51 PM, ARTHUR KELLEY wrote:
>>> I made an unplanned stop at the boatyard today to check my cover and
>>> remembered this thread. Since we have two boats in the same yard, I
>>> figured I'd check. Again, this was unplanned, so I was alone and
>>> did not have a ruler or tape measure but used a sail tie to compare
>>> the foils, and came back and measured the sail tie. Trends good,
>>> accuracy, not so much.
>>>
>>> The keels seem pretty similar, both faired to about 1/8" (Boat A) or
>>> a bit less on Boat B and both keels approximately the same length
>>> (depth) below the bottom.
>>>
>>> The rudders were a completely different story. Boat B appears
>>> "stock" with a fairly thick, rounded trailing edge. There is a
>>> school of thought that suggests that the rounder edge reduces
>>> turbulence when turning or when the rudder is offset from centerline
>>> like when going upwind with some weather helm. Then again the
>>> thicker edge does create more turbulence when running straight with
>>> the rudder on centerline.
>>>
>>> The rudder on the Boat A had been faired to about 1/8", the same as
>>> the keel, but to achieve this the trailing edge had been extended by
>>> about 2 1/4" to 2 1/2". This also affected the roundness of the
>>> bottom of the rudder. Both rudders seem to be the same length.
>>> Measuring from the leading edge of the rudder just below where the
>>> notch for the skeg ends, and running parallel to the top edge of the
>>> rudder (see attachment), Boat A's rudder measured approximately 28
>>> 1/2" and Boat B approximately 26 1/4". Remember I am measuring to
>>> knots in a sail tie here! Both were about 60" long, top to bottom.
>>>
>>> I photographed both rudders, traced them in the computer, then
>>> overlaid the profiles. The diagram (attached) is perhaps not as
>>> smooth and clean as they could be but this should be sufficient to
>>> get the general concept - and generate discussion. I would need to
>>> re-photograph the keels, the perspective was different and the
>>> overlay just did not work.
>>>
>>> I have not spoken to the other owner yet about what he knows about
>>> any modifications to his foil(s), so am keeping the identities of
>>> the boat anonymous for now. He frequently beats me, but I don't
>>> think that's raw boat speed as much as he and his crew just being a
>>> bit better than we are.
>>>
>>> Joyce, if you come up with your diagrams I'd be happy to post them
>>> on the class site, perhaps in the FAQ section.
>>>
>>> If anyone else wants to photograph their rudder or keel I can try to
>>> add those to the comparison. The photo would have to be taken with
>>> the camera aligned approximately mid-point on the foil and
>>> perpendicular to it.
>>>
>>> These specifications probably should have been more closely
>>> regulated in the early days of the class, but for now perhaps we
>>> should understand what the fleet looks like and try to avoid too
>>> much further deviation. In my mind changing the location of lead
>>> would be against the one-design rules so Bill, I applaud you for
>>> planning ahead for the event that someone wants to bring the boat
>>> back into class specs.
>>>
>>> Regards,
>>> Art
>>>
>>> On Thu, Nov 28, 2013 at 09:25 AM, Scott Marino wrote:
>>>
>>>> Joyce,
>>>> Sounds like those pics might be a nice additions to the Frers
>>>> website for all to see.
>>>> Scott
>>>>
>>>> --------------------------------------------
>>>> On Wed, 11/27/13, Joyce Oberdorf wrote:
>>>>
>>>> Subject: Re: [frers-list]Fairing keel and rudder
>>>> To: frers-list@lists.frers33.com
>>>> Date: Wednesday, November 27, 2013, 12:48 PM
>>>> Bill--
>>>> Here is what I know. When I bought Checkmate,
>>>> eons ago, we looked at 4
>>>> Frers 33s Each one had a slightly different keel and rudder.
>>>> Wolverine had a
>>>> less deep keel-- but NOT the "shallow keel" version.
>>>> Impetuous had a deeper
>>>> keel, faired to a fine blade, as was the rudder.
>>>> We measured with calipers the thickness of the trailing
>>>> edges. ALL
>>>> DIFFERENT>
>>>> This is apparently not covered by class rules. At that
>>>> time (way back in
>>>> the 90s), Impetuous was one of the leading boats, and the
>>>> owner, Paul
>>>> Zabetakis, was class president at the time. And close by. So
>>>> we decided to
>>>> go with that. We extended the rudder about 3 includes
>>>> to fair it from about
>>>> 3/4 inch to a fine edge. Did the same to keel. We didn't
>>>> have templates. If
>>>> I can find the diagram of the two boats we measured (I
>>>> plotted the shapes on
>>>> graph paper, I'll copy scan and email.
>>>> Joyce
>>>> On 11/18/13 1:44 PM, "Bill Thompson" wrote:
>>>>
>>>>> Hi all,
>>>>>
>>>>> Have sanded d'Ad lib's hull - waterline and below -
>>>> back to the vinyl ester.
>>>>> Brutal work. The good news is, after 27 years, not a
>>>> single blister, soft spot
>>>>> or other imperfection. Washed and wetted down there is
>>>> no ripple of
>>>>> imperfection to be found in the reflection. Come
>>>> spring, sealant and 6 coats
>>>>> of inter protect before bottom paint should keep her
>>>> dry and healthy for a
>>>>> good long time. Pics avail. if anyone would like to
>>>> see.
>>>>>
>>>>> However, keel and rudder (which is still dry) are not
>>>> as fair, so I'm
>>>>> wondering if anyone has templates and/or methodology to
>>>> suggest, so I can
>>>>> bring them fair, prior to coating and finishing. All
>>>> help appreciated.
>>>>>
>>>>> Bill Thompson
>>>>> Montreal
>>>>> _______________________________________________
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>> Art,
>>
>> Sure would appreciate the specs on the keels. I was told on purchase
>> that mine had been modified by a previous owner but now am not so
>> sure. My main concern is regarding the keel depth and it's effect on
>> boat performance.
>>
>> All thoughts and experience appreciated,
>>
>> Courtney
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