fater on one tack?

Submitted by KasbeKZ on Wed, 09/16/2009 - 16:16
the boat i sail as well as a few others at my club (rappahannock) are constantly complaining that we feel faster on one tack than the other. tacking from starboard to port feels like there's a 5 knot wind drop for the 4000 era boat that i sail. theories that i've come up with are that possibly the centerboard is slightly bent (not likely because it's just been out and faired by Mr. Neff, and we haven't gone aground since), one shroud is biased in length, or that it's just the old hull causing problems. i expect we'll take the mast down and measure each shroud to see if that may be the case, and i've just had the boat upside down painting and could see no defects in the hull. any advice on this matter would be appreciated. our sails are pretty fresh, with only 3-5 or so seasons on them, but this problem has persisted since they were new and with sails used in the past as well, so i put no blame on the sails. thanks in advance for any advice.
‹ rigging for racing Number of Races in Weekend Regattas ›

Comments

Make certain the mast is centered.

Submitted by David Lochner on Wed, 09/16/2009 - 17:05.
Make certain the mast is centered. To find out if it is centered, run a tape measure up the main halyard then measure to the base of the chainplate. The distance from the top of the mast to the base of the chainplates should be the same. If the distances are not the same, change the shroud attachments to make them even. I had a similar problem with a very old (1794) boat, the difference between the two sides was over an inch. It wasn't apparent from just looking at the shrouds or looking at the tension on the shrouds. I was able to reduce the difference to about 1/4" with much better performance.

ok thanks much.

Submitted by KasbeKZ on Wed, 09/16/2009 - 19:03.
ok thanks much. i'll give that a try next weekend before the race.

Certainly check for symetry in the boat with the mast being the

Submitted by karafiath on Thu, 09/17/2009 - 12:48.
Certainly check for symetry in the boat with the mast being the easiest to check and to correct. Is your jibtack centered? You should be capturing the forestay extension as well as the tack grommet when attaching the jib. Recognize that even if you capture the forestay with the shackle, the jib will be slightly biased to one side. Also the spinnaker halyard is generally led just to one side. However, you sail on the Rapahannock. Any small current or tide will instantly make the boat feel vastly different on the two tacks. The same with any wind driven waves that are not directly in line with the wind. I suspect that what you and others at your club are feeling are the current and wave effects. FS 3512

i had thought about the current issues as well.

Submitted by KasbeKZ on Thu, 09/17/2009 - 13:02.
i had thought about the current issues as well. though, on the last race, some boats reported being slow on one tack and others on the opposite. it was also pretty slack tide at the time. thanks for the advise about the jib. we have not been attaching the jib like that and we will begin. thanks much.

Your centerboard might be shimmed asymmetrically -- if shims pre

Submitted by Jay Lott on Tue, 09/22/2009 - 14:06.
Your centerboard might be shimmed asymmetrically -- if shims previously there have been lost -- so it's at a different angle to the axis of the boat on either tack. J. Lott FS 5698

well actually the center board has just been serviced in the las

Submitted by KasbeKZ on Sun, 10/04/2009 - 01:28.
well actually the center board has just been serviced in the last season or two. it was out, fared, and replaced by a well known guy. so i'm not sure that's the issue. i measured up the mast side to side last weekend and found that it's so very close that i couldn't make up for it with any adjustments that the boat offers.