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  #21  
Old 02-14-2012
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A practical experiment might help:

Roll-up enough genny to get it just shy of the shrouds. Then rig a temporary barber-hauler to try a number lead possitions. Use GPS to get tacking angles and VMG (pick a no-current time or location).

With the wieght and full keel it is very possible that narrow angles won't help.

Also, there may be many trim combinations that effect balance and helm that you haven't tried. Often pacing (trying to pass) a similar boat while you try changes (twist, traveler, outhaul, downhaul, and sheeting of sails together) is very educational. When I changed to a new boat a few years ago--and I was fast and competative on the prior boat--I was stuborn about changing my sail trim habit, even though they were equite wrong for the new boat. Then one day I was sailing near a similar design that was creeping away from me, retrimmed (looser for the most part) and walked away.

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  #22  
Old 02-14-2012
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In addition to the genoa track, which allows the sheet blocks to be positioned over a long expanse, my boat has blocks on the deck, inside the shrouds which I use for the working jib. The jib needs to be sheeted in much closer than the genoa to attain best efficiency and will not set at all using the track. Using the working jib and interior blocks is really is my favorite sail setup in anything but a very light wind. This configuration seems to balance much better than the 160 genoa. I think many use a gigantic genoa when a smaller headsail would make their life easier. I realize that more modern boats are designed for genoa rigs with smaller mainsails but less canvas in the headsail may be a solution to balancing problems, especially in winds>15 knots. I also like the fact that a jib rolls up much smaller, with much less weight. With just a couple of rolls, the jib can get very small.
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  #23  
Old 02-14-2012
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The last few posts give good advice.

Suggestion is made to set up some 'trials' (with or without a 'trial horse' boat for comparison) with data collection of speed, AWA, VMG, % of overlap, etc. etc. on various combinations of sails and trim, etc. etc. to attain the optimum sailing angles. Such plotting and analysis of raw data will allow you 'empirically' arrive towards 'optimum'.
This would include using (temporary) barberhaulers to manage the jib, etc. sheeting angles.

For staysail usage in/for the trial Id recommend going to www.arvelgentry.com --->magazine articles ---> "double headed rig" to get you to a starting point for decent staysail luff shape (heavy luff/halyard tension) to affect good aero flow to main and topsail, etc. .... this is probably the only valid/correct work ever done on the interaction of staysail w/ main w/topsail. This implies that 99% of all staysails have wrongly designed (broadseamed for a 'sloop') shape, and what you can do about it .... hard luff tension!!!!
All of the above will obviously depend the targets of 'helm balance' (by correctly positioning the point of max. draft via halyard/boltrope tension) AND proper headstay/forestay tension to match the 'luff hollow' that has already been cut into all your present headsails. Any rig with 'multiple' headstays, solent stays, forestays (staysail stays) will ALWAYS have/present a wire tension 'nightmare' in getting all those tensions/sags to match the luff shape to get to 'optimum' output .... sometimes you have to get the luff shape (luff hollow) re-cut to attain this 'match' and so you dont have to apply adverse stay tension (>~25-30% wire tension for wire FATIGUE considerations). To 'point' with any efficiency youre going to have to get all these various wire tensions correct and balanced with respect to sail shape, etc. to arrive at a suggested target of quite 'neutral' helm, .... and then 'backoff' to get ~3° rudder angle so to get 'any' possible lift to windward out of a loooong keel --- yeah, its possible to get some 'lift' from a looooong keel when closehauled, ... can be done and your VMG will thank you.

FWIW ... use a wire tension gage to monitor the max developed wire tensions when fully sail loaded ... and use 30% MAX. tension when at max. heel (~45° over) as your rig's structural 'limit'. This will keep the rig UNDER/BELOW the "fatigue endurance limit" (~30,000 psi for most 300 series stainless steels) and prevent sudden/catastrophic fatigue failure. Riggers dont make emergency service calls out in the deep ocean.

Here's some articles Ive written that will probably apply to your boat:
•"Matching forestay/headstay tension to 'luff hollow'" - http://i1086.photobucket.com/albums/...LuffHollow.gif

•"HOW to properly RAISE a boltroped woven dacron sail" ... discussion is proper boltrope tension: How to properly RAISE a woven dacron mainsail - SailboatOwners.com

My suggested 'preliminaries' would be to get the optimum shape/trim of the sails and wire tensions (based on sail shape, etc.) to get to a 'neutral helm' (rarely involving 'mast rake'), followed by trials with barberhaulers, etc. on the foresail(s) to get to a maximized 'close hauled' VMG, etc. .... the recorded data from many 'trials' will show you 'which way to go'.

hope this helps. ;-)
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Last edited by RichH; 02-15-2012 at 12:33 AM.
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  #24  
Old 02-14-2012
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There is really alot of wonderful info on sail trim in this thread. One extra point is what is used in some small boat racers a Barber Hauler. It is the extra sheet that pulls the clew windward. If you do get that sail then you have to make a big decision as to where to put the track, how to properly mount it, etc. However an extra sheet attached to the clew will allow you to close the angle until it looks right with out installing a track. Remember the luff must not be too loose so that the draft moves aft and backwinds the main. The max draft needs to be in the sweet spot depending on the boat. Twist the leach of the headsail to match the twist of the main and keep the slot uniform from top to bottom. Sail fast!
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  #25  
Old 02-14-2012
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Despite all of the well meaning advise, I don't see how you can really do much meaningful testing. For example, if you were going to move the jibsheet lead inboard, you would need a jib cut with a full length luff, and moderately full entry that would be cut so it did not hit the spreaders. You would then need a mainsail cut to work with that jib.

Roll furling the jib, would result in short luff and a poor sail shape for beating, and you still have a full cut mainsail so the data would be next to useless. Barber hauling the jib would work on a boat with narrow spreaders but on a rig like this it would only pull the sail into the spreaders and/or hook the leech so again the data would be next to useless.

In the end, the best advise given is replace your sails if they are old and blown out, getting new sails will make a huge difference. Get them made by a sailmaker who cares about you and who understands your concerns. Get them designed for the realities of your boat. Get them made from a low stretch fabric. And that is about all you cna do to improve windward performance on a boat like yours.

If you really care about pointing ability, (or any other modicum of decent performance sailing for that matter) then you need to consider buying a boat that was designed to perform. That means less drag, more length for the displacement, a more efficient rig and hull.

Otherwise, I suggest that you focus on the realities of the boat you own, and love her for what you percieve as her virtues and quit worrying about her short falls.

Respectfully,
Jeff
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  #26  
Old 02-15-2012
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Quote:
Originally Posted by Jeff_H View Post
Otherwise, I suggest that you focus on the realities of the boat you own, and love her for what you percieve as her virtues and quit worrying about her short falls.

Respectfully,
Jeff
Don't worry, there's no lack of love for the reality of my boat. Seen my sig?

I'm not worrying about windward performance at all. Rather I was planning on installing the staysail stay anyway, and this idea was tossed my way as a easy addition. If it ain't easy to do, or if the windward performance he saw was imagined (a very real possibility) then I'll can the idea, but it was sold to me as something simple and cheap to do, so I thought I'd see how valid the idea is.

I agree though that testing, while ideal, is not really practical. There's so much current around here too that comparing one setup to another and looking at the VMG won't mean much.

Also I was on the boat today, eyeballing things, and I realized that if I were to sheet (and fly the sail) inboard of the shrouds, the sail can't overlap the main by much because it'll hit the spreaders. If I fly the sail outside the shrouds, well, that's what I currently have. I guess when I was visualizing this overlapping staysail inside the shrouds I forgot about the spreaders being in the way....

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  #27  
Old 02-15-2012
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Med --

The Garden Formosa 41 normally is set up as a double headed rig with headstay and forestay. This headstay/forestay combo is perhaps the *main reason* why such a combo has poor pointing ability ..... automatic 'interplay' and load sharing of TWO forward stays vs. 'any' backstay, etc. combo.

What happens to lessen pointing ability is, especially when flying a much larger SA headsail 'over' a smaller staysail, the windloading on the headsail will transmit its resultant forces into the forestay and the headstay will correspondingly unload which will cause the headsail's luff to shift towards the leeside .... and which causes the leech of the headsail to become hooked to weather and also for the position of max draft to shift aft.... and correspondingly the forestay tightens and the (fore)staysail will be closer to the CL than as designed/cut. The result is increased aggressive heel and the boat will begin to SKID off to leeward (and the helmsman will erroneously blame weather helm) ... and with a corresponding significant loss of boat speed.

So, to make such a double headed crab-crusher 'point', you will find that (whether flying the staysail or not) to make such a boat point (and not skid) you will have either:
1. to ease/slacken the forestay (which automatically tightens the headstay in 'reaction') so that the heaadstay luff remains close to the boats centerline AND that the headsails luff curve matches the sag in the headstay wire ---- when 'beating'.
OR
2. Sail the boat like a sloop and with the forestay completely removed/detatched ... so the headstay remains at a near constant 15%± tension to match the sag/hollow that the sailmaker cut into the luff of the headsail.
OR
3. have the headsail's luff recut with additional luff hollow to accommdate the 'normal' sag of the wire (based on actual observation/measurement of the wire 'sag') to match when the headstay IS 'unloaded' when beating.

Ive done this with quite a few double headed rigs over long distances and by 'trial'/data accumulation over a very long time .... can increase pointing ability by upwards of 12°++ as when compared to a double headed headstay/forestay boat with the rigging tuned 'like a sloop'. ... that alone will give you about a 20% better VMG out of the starting blocks. At 6kt. average boat speed that means a 170 Nm day instead of a 144Nm day .... when 'beating'.

The same 'problem' is exacerbated on boats with Solent Stays, etc. - stay/wire 'load sharing' and unloading of the stay that carries the more windloaded sail. This is, to me, the main reason that cutter rigs and solent rigs cant POINT as well as when simple sloop rigged. If one makes the proper 'corrections' then you can come 'close' to the pointing ability of a sloop (of the same/similar underwater configuration, etc.)

Rx: it isnt the sails (new or old) that make a double headed rig so 'unweatherly', its the damn variable headstay tension.
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Last edited by RichH; 02-15-2012 at 11:23 AM.
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  #28  
Old 02-15-2012
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I've been eyeballing going to a hank on Yankee to fly with my Staysail since getting my butt kicked on a distance race within the San Juan's some years back. I hate furlers and love being able to quick change sails. I still may go this route.
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  #29  
Old 02-15-2012
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RichH- I understand what you are saying but you don't mention the use of running backstays which should alleviate (to some degree) the unloading of the staysail stay shouldn't they? I know that I was having problems similar to what you are describing prior to having a knowledgable rigger rake the mast differently and re-tune the rigging as well as improve my runners so they can be used with the offside sheet winch. Pointing, and weather helm, has improved quite a bit after these changes. My boat is a cutter rigged sloop with furling on both headsails.
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  #30  
Old 02-16-2012
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RichH,

Great explanation. I can absolutely see how that would cause forestay and headstay tension issues. I'm sure the problem will be exacerbated by my using a soilent stay instead of a cutter stay, and probably also worsened by my twin back stays instead of a split backstay.

I probably haven't been clear enough though about one point. I do NOT intend to EVER fly 2 headsails at the same time. The idea as suggested to me by the other owner was to fly a foresail from the staysail stay instead of the headstay for better overlap and sheeting ability.

Some Formosa 41s and all CT 41s (nearly identical sister ships) have double foresails but I have no need to divide my foresail effort. My rig is devided up nicely for my taste as a ketch. The original reason to add the soilent stay, before I got on this track, was for a storm jib.

So I still feel like the original question still lingers. Assuming I have a headstay and a soilent forestay to choose from, will I go to weather better with my 120% genoa flown from the headstay, or will I go to weather better with a smaller, purpose cut foresail flying from the soilent forestay and sheeted to the cabin top?

MedSailor
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