Best Pointing adjustments

[Joe Nelson CS#35]

Wondering what the best sail and centerboard adjustments will produce the best pointing ability for the cat ketch?  I know these boats are not known for pointing as their best feature...but getting all you can get is important.  I race a Lightning and as sloop rigged, they will tack through 90 degrees or less.  We scallop up and hook the top main batten for gaining pointing ability, then let off the main sheet a bit and gain speed again.  The scallpping does net you more distance made good than just keeping the boat speed up.  Helm balance and pointing is improved though keeping the boat heeled to leeward.  This digs the chine into the water and presents a different hull shape than sailing flat does.  Helping to force the hull up without any rudder drag.  I get great input and practice every week with the Lightning, but the Core Sound doesnt get as much use. 

Next year I think I will enter the single handed races at our club with the CS20.  Should be fun!  The Core Sound 20 has a very similar hull shape to a Lightning.  A bit shorter 19'+ and a couple inches wider.  I bet Graham would like the royalties on 16,000 boats.  Speaking of a designer hitting the jackpot...How about Bruce Kirby...He gets $100 royalty for each Lazer and they are over 200,000 and counting.

[Howard]

For those of you with Cat Ketch rigs, how well do they point? I'm thinking actual course made good to weather as measured by a GPS.

On my Montgomery (a masthead sloop), which wasn't designed to be a racing boat, but has a good track record doing that, I can't do much better than tacking through 100 to 115 degrees actual, at least on my GPS. Compass says about the same thing. You can get to weather, but you have to tack some to do it. The masthead Windex is set to about 90 degrees and you appear to be tacking to that (to the apparent wind anyway), but actual course made good to weather (with leeway factored in) is as indicated above. And I don't give up much to the fleet I sail with (a variety of sloops...both big and small)...so I don't think others do much better than that, despite what folks say about tacking through 90 degrees. 

I suspect that as long as you are getting to weather (and doing it fast), you may not be giving up as much ground as you might think.

[mustangermatt]

I was trying to beat around Marrowstone pt to Port Townsend a few weeks ago, against 2 1/2 - 3 knot current, about 10-15 knt wind.. I couldn't make it quite around the point, but could hold position. I found staying a little off the wind and keeping boat speed up worked better than trying to point as high as the boat can go. I was getting to within 50 feet of the beach so I had a very good reference as to distance made good, or not made good in this case :-)

[JeffM]

I can't do Ray's point-abeam thing.  Last trip (overnight on Lake Pepin) my best tack (read off gps tracklog screen with a protractor, since I wasn't paying attention to the compass at the time) was maybe 105 degrees.  115-130 is pretty typical when I have all telltales streaming--though I've found that pointing higher and letting the windward telltales stall doesn't hurt speed.  I probably have a lot to learn.  I find I never mess with the downhauls and generally have the snotter in pretty flat.  I only mess with cb angle (other than pulling it up downwind) is if I have to hold the tiller at an angle (severe lee helm).  Oddly, I have seen lee helm in very light winds or reefed in moderately light winds--but only on port tack.  Probably my assymmetrical hull.  ('Course I meant to do that!)

[mustangermatt]

Or, you could get a fix at the start of you tack by triangulating, then note your heading, then get a fix at the end of your tack and compare the compass course to the course made good to get your leeway. Then you don't have to fork out 500 bucks for a gps. Call me cheap :-)

[JeffM]

Actually, Ray, I was referring to my gps "compass," which shows course made good.  Measuring the angle on the track display allows averaging out the inevitable little bobbles, but I'm not sure how accurately my display represents actual physical positions.  For example, suppose one cm in the vertical direction and one cm in the horizontal on my Magellan's screen were not exactly the same distance over ground?  Probably not worth worrying about, but I try not to take too much for granted.  Probably the "cadillac" method would be to fix my position by gps at the end of each tack, plot them on a chart, then take the angles off the chart.  Same as Mustangermatt, but with nifty technology to make it faster and more accurate!  Regarding leeway, wouldn't any significant leeway show itself in a noticeable angle between boat and wake?

Ray, gps is a miracle--even more when you find out how it works.  I took your advice and bought the bottom of the line.  The first time I used mine it was to find my way to a point too far away to see in unfamiliar waters in the dark.  Made me feel I could go anywhere I wanted any time I wanted.  (I've since learned better.)  I just hope I still remember how to recognize aids-to-navigation in a few years...

[Howard]

On the GPS, I have two units. One older handheld and one new one that also has depth. The screen shows navaids, etc. A great tool, but don't forget the compass and charts and don't forget how to use them. That great tool doesn't work if the battery is dead.

My idea for using a GPS to determine your course made good was a bit easier. Simply take a GPS heading on one tack....say 270 degrees (due west)........then a heading on an opposite tack......say 180 (due south) and the difference is 90 degrees. If the opposite tack is only 170....you are tacking through 100 degrees. As Ray correctly mentioned, this is only a reliable method in water with no tide or current. Throw that in and it all changes due to drift and set of the current.

When you think of the variables present....... speed (which varies), course heading (which varies), leeway, drift and set of tide or current (which changes as the day goes by), accurate navigation without GPS was and still is a chore. I suspect that locked in a fog bank without reference to navaids, or the ability to fix a position from shore references, most of us would be in bad shape. And that is before the tanker we can't see coming arrives.

[JeffM]

Roger that last bit.  Nearly all chart info was collected WAY before gps, and its accuracy can vary widely.  Ray, I've tried your compass rose trick, but find that, around here, simply reading the lat or long and eyeballing it on the chart(usually I'm in a passage, so only one or the other is needed) is fast and easy.  Also handy is the fact that 1 min of latitude is 1 nautical mile, so I don't have to go to the edge of the chart too often.