Wind vane - angle of reference tabs

batami

.
May 24, 2015
16
Tahiti 40 ketch Singapore
I am a sailing Newbie. I have a 12m Tahiti Ketch. There is no Wind Vane fitted so I have purchased a Davis Windex Wind Direction indicator. The instructions tell me to adjust the reference tabs angle: "55 degree for boats with extremely good windward performance, 60 degree for normal ocean racers, 65 degree for auxiliries and similar types". Ocean racer she is not; I suspect that the angle should be 65 degree, but can anyone confirm please,
 

Joe

.
Jun 1, 2004
8,161
Catalina 27 Mission Bay, San Diego
Set them at 65 and then forget it, because you should be watching the tell tales for trimming your sails.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Joe called it. A windex is a sanity check instrument, simply another datapoint regarding what the wind is doing around your sails. Watch your telltails.
 

DougM

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Jul 24, 2005
2,242
Beneteau 323 Manistee, MI
It doesn't really matter where you set the tabs, the windex is merely a redundant check if you have telltales on the sail. After awhile you will get a sense of the relative position of the indicator arrow in relation to the tabs wherever you choose to set them. Besides you will get a stiff neck if you keep looking up to the masthead.
 

batami

.
May 24, 2015
16
Tahiti 40 ketch Singapore
I am answering myself, now that i have trawled Google. Seems that for a long keel Tahiti ketch, clause hauled might be, optimistically, 65 degrees. i am reading that set at 80 is probably a better idea ..... still looking for advice / comments from you experinced sailors out there

Bill

I am a sailing Newbie. I have a 12m Tahiti Ketch. There is no Wind Vane fitted so I have purchased a Davis Windex Wind Direction indicator. The instructions tell me to adjust the reference tabs angle: "55 degree for boats with extremely good windward performance, 60 degree for normal ocean racers, 65 degree for auxiliries and similar types". Ocean racer she is not; I suspect that the angle should be 65 degree, but can anyone confirm please,
I am answering myself
 
Feb 20, 2011
8,048
Island Packet 35 Tucson, AZ/San Carlos, MX
Sure, set it at 80 degrees. It'll make you think your vessel can point like nobody's business. ;)

But seriously, if this is important to you, you'll be going up the mast to readjust the arms to your particular observations, don't you think?
 
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Jul 27, 2011
5,134
Bavaria 38E Alamitos Bay
Take the boat out, determine your best average tacking angle [by looking at your compass] from close-hauled to close-hauled on opposite tack by referencing tell-tails; e.g., if tacking on average through 130-deg set your Windex reference tab angle accordingly (i.e., 130/2 = 65 deg) then install it. Make sure it's on straight! If you ever buy new sails, you might have to change it.
 
Last edited:
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Take the boat out, determine your best average tacking angle [by looking at your compass] from close-hauled to close-hauled on opposite tack by referencing tell-tails; e.g., if tacking on average through 130-deg set your Windex reference tab angle accordingly (i.e., 130/2 = 65 deg) then install it. Make sure it's on straight! If you ever buy new sails, you might have to change it.
Not quite right..... tack-to-tack compass difference /2 gives you your TRUE wind tacking angle. The vanes are set to APPARENT wind tacking angle and that angle is always tighter that the true angle.
 
Jul 27, 2011
5,134
Bavaria 38E Alamitos Bay
A boat sailing a course 50-deg off the true wind of 10 kt, making 6 kt, would have an apparent wind angle of 32-deg. So, we're saying the Windex reference tab would therefore be set at ca. 65-deg? Could this ketch really sail 32-deg off the apparent wind; even 40 deg (w/ tabs set at 80-deg)? Maybe 110-deg is the answer!
 
Last edited:
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
A boat sailing a course 50-deg off the true wind of 10 kt, making 6 kt, would have an apparent wind angle of 32-deg. So, we're saying the Windex reference tab would therefore be set at ca. 65-deg? Could this ketch really sail 32-deg off the apparent wind; even 40 deg (w/ tabs set at 80-deg)? Maybe 110-deg is the answer!
Could it? Sure. That's pretty typical for AWA tack for most boats.

In 14 knots of breeze my First 260 sails into 37 degrees true wind and tacks through 74 degrees TRUE. 52 degree AWA. That's very weatherly. We use the very narrow settings.
 
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Oct 26, 2008
6,240
Catalina 320 Barnegat, NJ
I'd have a permanent kink and a stiff neck if I was looking at a wind vane. Never had one, never wanted one. But I do look at the wind instrument display and find it useful.
 
May 24, 2004
7,164
CC 30 South Florida
No need to take out your slide ruler and get into extensive calculations nor be exact on the methodology to obtain the best angle as all you are seeking is a good enough calibration given the non-precision of the instrument. After all through repeated observations your mind in time will learn to better calibrate the results.