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Old 30-09-2008, 04:45   #31
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So I assume you are using GPS.

With a gps you can have marks wherever you want.

Set two waypoints at least a mile or two apart that line up into the wind and preferably into the swells.

Tack across this course line. When you are crossing the course line note SOG and VMG on either tack.

The only time you are getting apples to apples on VMG is when you are crossing a course line that is oriented into the wind.

If you are on port tack and right of the course line you are driving away from the mark and VMG will be lower than starboard tack right of the course line.
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Old 30-09-2008, 10:32   #32
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We all know a dog can point, but now you say a cat? Love to see a pic of that
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Old 30-09-2008, 11:03   #33
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I have a friend with a 39' full keel boat and we were sailing in the Neuse river last weekend. I pulled up next to him because he wanted me to shoot some photos while his boat was under sail. After we took the photos I fell off on a reach in relatively light air and he pointed up a bit. He called me on the cell phone and gave me some crap about my cat not being able to point. I had suspected that his full keel boat might be able to outpoint me, so I decided to see what we could do. I pointed up, passed him, and crossed his bow a good 10 degrees closer to the wind than he could manage. All this in my endeavourcat 44 Condomaran. Yes, cats can point, Even the boxy ones!
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Old 30-09-2008, 14:06   #34
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Hey Sarge,
depending on the sail plan the mizzen can add a lot of drive, give balance to the jib, and also help you tack without having to backwind the jib (picture the wind pushing the ass end around). Sheeting angles, traveler position, the cut of the sails, head stay tension, etc....can have a lot of effect.

I would suggest VERY strongly to keep the mizzen and use it, it's there for a reason. Work with what you have and once you have it all sorted out you might consider having the sails looked at by a loft that has real experience with multihulls. Flatter is better than fuller to work to weather.

The cross 38s are very pretty boats, are of a proven design, and should perform well.
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Old 30-09-2008, 14:56   #35
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This thread has lots of talk, mostly with people quoting silly numbers about apparent wind angles. WHO CARES?
Well, I think it's actually a good starting point. If, you've followed this thread, you'll have noticed that his pointing ability is not the same on port and starboard tacks. When this is the situation , it matters little if we are talking sailing off of apparent or true wind. Regardless of the tack, the boat should perform the same.

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Even better, lets start talking about what REALLY counts, and that is VMG parallel to the wind.
Why? We aren't discussing 'my boat is better than your boat'. The problem is the boat performs better on one tack vs the opposite tack. I'm certain that suggestions to narrow the problem down are welcome, but don't understand why you're taking this tact (please excuse the pun).
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Old 30-09-2008, 15:49   #36
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Merlin will you be at HYC this Friday?
Sorry, Sarge

I live on Kauai
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Old 08-10-2008, 00:32   #37
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Well folks, thanks for all the advice. Unfortunately I couldn't put it to use for reasons I won't go into. Crew problems mostly. This week end I will have some decent crew to set things up. I did some tacks using the compass, Port tack was 30 degrees Magnetic and Stbd was 150 Magnetic. This weekend I plan to lay out a course into the wind as recommended. I may have to get some wind instruments. What is the opinion of the Tick Tack stuff.
Robert I see you have a Kantola, I missed out on a 38 I believe it was here in the Islands. There is presently a Kantola in the Marina at Sand Island. Talk about pretty boats. Always loved those Kantolas.
Merlin If I get to Kauai we will have to have a sail. Of course that requires getting this pointing problem fixed. As It is I would have to sail a fair distance north to get back to Oahu.
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Old 08-10-2008, 00:41   #38
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So if the magnetic wind was 090 then she is pointing 60-60. Not great but...

With a speed log you can determine boat speed on each tack

With a gps and a waypoint to windward you can gather VMG

I'd work tack angles and boat speed first
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Old 08-10-2008, 01:08   #39
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What was disconcerting was the GPS showing me headed more or less back where I started. Not good for getting to weather.
Rich
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Old 08-10-2008, 01:12   #40
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I will try playing with sheeting, maybe try to rig a barber hauler to change sheeting angles. Tighten the forestay. Although it is pretty tight. Suggestion by the other multihuller who sailed a Nicol around the world is the sails are just cut to full for the local winds. The boat also tacks very slowly. Must be that long mini keel.
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Old 08-10-2008, 04:31   #41
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RYA Instructor advised the Benetau he rode recently made up to 30 degrees leeway.
It might point well but it sure don't go to windward!
Cats slip around 5 degrees if boat speed is kept up so add a factor to your point and get a real figure. GPS reading of VMG (velocity made good) is the best indicator and doesn't lie. Add a tidal prediction to be sure of what you are stating.
No good planning voyages if you don't know what your boat actually does!
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Old 08-10-2008, 04:59   #42
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Ouch, that indicates your upwind vmg is zero.

Try barber hauling inboard, traveler down some, parrelel the top batten to the boom, move the draft back to 40 to 45%. Try sailing fat and shy too see what your boat likes.

Enter in your gps an upwind mark ~100 miles away and try different trim options. Watch your vmg to that mark, record what works, but be cognizant of wind shifts (ie look at vmg on both boards)

Good luck.

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What was disconcerting was the GPS showing me headed more or less back where I started. Not good for getting to weather.
Rich
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Old 08-10-2008, 07:07   #43
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I may have to get some wind instruments. What is the opinion of the Tick Tack stuff. Sarge
Tack Tick:

Easy to fit.

fine if you only sail in the daytime as the battery doesnt last through a complete night (or even more than an hour on the boat I last sailed with tacktick)

Prefer the more conventional approach to this with proper seperate speed and direction sensors.

If all else fails, a windex at the mast and a couple of strands of wool on the shrouds is enough to provide the information needed. Anything else is just additional refinement.
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Old 08-10-2008, 07:25   #44
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Tack Tick:
Easy to fit.
fine if you only sail in the daytime as the battery doesnt last through a complete night (or even more than an hour on the boat I last sailed with tacktick)...
Tacktick automatic solar charging regime:
Bright Sun 2 Days
Cloudy Days 5 Days
Dull Days 10 Days
It is not possible to recharge the battery with electric lighting sunlight must be used
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Old 08-10-2008, 07:43   #45
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The first time I sailed on open water I had a problem just like that. Then someone pointed out to me that I was on a tidal river, and I had forgotten that the water under me was moving too. Combined with the wind shadows of the trees on both sides, the peanut trail on my gps could never be a pretty zigzag stitch!

To measure your problem, take a magnetic reading with a good handheld compass when you pass thru head to wind on a tack. Get the boat moving again, and record your heading. Tack a few times, recording your heading each time after getting the boat back up to the same speed, then get another straight into the wind reading. This is your raw data. cozy up to a channel marker and note the direction of water flow. take this data home and check the tide predictions to confirm the flow you noted around the marker.

If you do end up with more that ten degrees difference in your ability to hold the same speed on different tacks, you have a problem under the waterline. It may be a result of a slightly assymetrical shape in the keel foil, or a missalignment in the akas.

Unless there is a gross discrepancy in the mast's lateral measurements, an error of that magnetude can't be fixed with tweaks to the standing rigging.
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