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Author Topic: What I learned this season  (Read 17999 times)
Ken Smith
ADMIN

Posts: 289


sail often, travel light


« on: March 08, 2007, 07:42:19 AM »

I learned a great deal (who'd have thought after 20 years) the week leading up to and during the Worlds.   Since I have to write it down to remember it, I figured why not here.  So this is the outline, and details will follow.  Please feel free to comment or add your tidbits.  I am still learning.

Major lessons.  Details to follow later:

1.  Clear air is worth two or three tacks on the first upwind leg.  Said another way, two extra tacks are worth it if you get clear air as a result.  It is essential on every upwind leg, but the chance to miss clear air is greatest on the first upwind leg.

2.  Trickling into the weather mark is a killer.  Overstanding and roaring into the weather mark is much better.  AND more fun.

3.  A poor start can be overcome by sailing fast, ducking sterns.  Also see 1.

4.  Sailing for a few days and tuning with fast sailors results in learning how to sail in many conditions.  Heavy air:  Slightly more mast rake, tight shrouds, and powering-up downwind are the highlights.  Lighter air, mast more upright and looser shrouds is fast.


5.  You have to sail three laps of a three lap race to finish in the top 12.

6.  Once optimum is found, the side stays do not have to be changed.  Tune with forestay tension and mast step location.

7.  Nailing lay lines is worth a bunch.

8.  Detecting and responding to wind shifts is worth a lot.  Especially down wind.

9.  To ride the rocket sled down wind in heavy air requires sharp runners, careful steering, a boat with zero slop in the steering [and cajones].

10.  There is no excuse for a wide mark rounding at the leeward mark.  See 1.

{11.  Never leave the main too low!  In most wind, you can't get the leech tight enough if the main is too low.  Can't accelerate and can't point, and have to fall way off to bend the mast.  [I forgot that rule as I did not make that mistake all week]}

« Last Edit: December 02, 2007, 08:56:49 AM by Ken Smith » Logged

Ken Smith
DN4137US
Paul Goodwin - US 46
ADMIN

Posts: 100



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« Reply #1 on: March 08, 2007, 10:03:13 AM »

A great compilation of tips and observations.  However I might take exception with, or at least qualify,  one of your tips:

4) Mast rake: in good strong wind (the stuff that tests your resolve to compete, like the 1st Gold race of the 2007 Worlds) I rake forward to reduce bend - too much bend isn't fast, especially if you need help to drag the carnage back to the finish line.  At the other end of the spectrum, in really light wind, rake back to help promote mast bend - if you can't get the mast to bend, you'll never reach warp speed.

Also in 4), tight shrouds, loose shrouds - contradicts a bit with 6).  If you don't adjust shroud length as suggested in 6), then more mast rake = looser shrouds, less mast rake = tighter shrouds.  These two go hand in hand because less mast rake = less mast bend + tighter shrouds = less mast bend.  So --- shorten the forestay and it does double-duty (for less mast bend) by giving tighter shrouds + less mast rake.

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Paul Goodwin
DN US-46
Ken Smith
ADMIN

Posts: 289


sail often, travel light


« Reply #2 on: March 08, 2007, 06:16:35 PM »

Paul:

I certainly agree with the theory.  However, in several high-wind scratch races, more mast rake (moving the mast base forward 2 inches) was, by experiment, faster.  Base forward and forestay tight are contradictory, but faster by experiment in fast ice and high wind.  I suspect the additional bend (and lower sail) moved power lower, allowed actual increase in speed and reduction in upsetting moment.  The tighter shrouds kept the rig straighter than it could have been under my weight and the wind load.  The plank was already very bent by pre-loading the tight fore stay.  I also lowered the main on the mast.  Hay, consider the context.  I was in Bronze based on rank, and did well in every race.  I would have lost my socks in Gold, most likely.

This brings up another lesson learned:

11.  Never leave the main too low!  In most wind, you can't get the leech tight enough if the main is too low.  Can't accelerate and can't point, and have to fall way off to bend the mast.  [I forgot that rule as I did not make that midstake all week]

Was my set-up truely fastest?  Who knows, but the changes increased my speed reletive to the Polish competition in scratch racing, and proved to be very fast in the fleet racing during the worlds.  I felt good and under control, worth some cajones down wind in the rocket sled.

When I say Loose/tight shrouds, without adjusting them, I really mean loose/tight forestay.  I use a Sta-lock turn buckle with a handle, and can easily tighten or loosen the forestay.  Let's define terms.  Tight shrouds = forestay tight enough that when I stand on the plank, the shrouds are still tight.  Twang.  The plank is pre-bent past straight by the tight forestay.  I can tell by the feel of the forestay turnbuckle when I am in this condition.

Medium shrouds = when I stand on the plank, the shrouds are still straight, but most of the tension is gone.  Thwaa.  The pre-bend in the plank just about removes all the crown.  When sailing, the wind load causes some slack in the side shrouds.  For my mast and weight, this is the 8-10 mph shroud setting.

Loose shrouds = just slack in the relaxed plank condition.  Very slack in the sailing condition when some speed has developed.  The shroud adjusters lay on the plank under sail.  Light air.

My tuning sessions showed that the the fastest was with the mast base in a particular location in all but the heavyest wind conditions.

Other tuning combinations can probably achieve similar results, but this combination allowed me to have the boat set up and on the starting line.  If the wind seemed to have diminished or increased by the start, a quick six-turn adjustment of the fore stay tuned the whole boat.  The only substantial rig change came if the wind was very high.  Mast step adjustment is too much for an on-the-line change.

Worked for me, I had a BLAST all week!
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Ken Smith
DN4137US
Ken Smith
ADMIN

Posts: 289


sail often, travel light


« Reply #3 on: February 20, 2016, 06:28:12 AM »

What  a great review article!  Love search feature.
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Ken Smith
DN4137US
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