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Old 17-09-2016, 21:04   #31
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Re: S2 9.2A Poor Pointing Ability ??

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Originally Posted by JIvories View Post
And according to a good sail maker in RI, a good racng headsail, a good traveller, a smooth hull, and maybe a folding rudder would speed her up enough to be competitive. For some $$, clearly.
Couple things, I think you meant to say folding prop right? Or a balanced spade rudder (that would be major surgery and lose the cruising advantage of a skeg-hung rudder's somewhat greater strength... and I do know some threads here have debated that though.)
The other thing is, there was a great Max Ebb article a couple years back in Latitude 38 called "minding the gap" I think that went through the importance to pointing ability in having the foot of the genny as close to the deck as possible to keep the wind from escaping out the bottom. A boat with a roller furling headsail probably has a huge gap.
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Old 17-09-2016, 22:58   #32
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Re: S2 9.2A Poor Pointing Ability ??

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Couple things, I think you meant to say folding prop right? Or a balanced spade rudder (that would be major surgery and lose the cruising advantage of a skeg-hung rudder's somewhat greater strength... and I do know some threads here have debated that though.)
The other thing is, there was a great Max Ebb article a couple years back in Latitude 38 called "minding the gap" I think that went through the importance to pointing ability in having the foot of the genny as close to the deck as possible to keep the wind from escaping out the bottom. A boat with a roller furling headsail probably has a huge gap.
The "gap" is definitely something that you want closed. I guess I didn't get into any depth on it, thinking it to be common knowledge, mistakenly (of course). But it's what I'm referring to when I briely mention an end plate seal on the jib, with deck sweeper jibs, up above.

Basically what happens with a jib which is tight against the deck, is that the wind in it isn't allowed to spill through underneath of it. And in addition to the extra bit of power this alone would give you, this configuration also improves the aerodynamic efficiency of a sail greatly. Especially in lighter airs, when using your big headsails, which is when you need the power most.
The gain in efficency is due to there being more lift, & less drag being created by the sail. And it's working the same as do the fins out on the ends of airplane wing tips, as mentioned in one of my posts above.

It seems a small thing, but when you sail against a similar boat to yours which has a jib that's flush to the deck, & you don't, you definitely notice. And more on it is discussed in the Dashew's Offshore Cruising Encyclopedia, Vol. II Where they get into some of the whys that drive it, & pro's & con's of having it or not for a cruising boat.
The books are free to download at www.setsail.com
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Old 18-09-2016, 13:54   #33
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Re: S2 9.2A Poor Pointing Ability ??

Yes, meant folding prop! Sorry.

Good to know about the Cruising Encyclopedia. Looking forward to downloading.

About the gap, and the advantage of having genoa flat to deck. I don't think
any roller furlers will allow that.

See these pics on Sailboatdata.com of S2 9.2. I'm wondering if it's possible to get good upwind genoa shape with shrouds so outboard, close to lifelines.

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Old 18-09-2016, 14:27   #34
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Re: S2 9.2A Poor Pointing Ability ??

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Originally Posted by JIvories View Post
Yes, meant folding prop! Sorry.

Good to know about the Cruising Encyclopedia. Looking forward to downloading.

About the gap, and the advantage of having genoa flat to deck. I don't think
any roller furlers will allow that.

See these pics on Sailboatdata.com of S2 9.2. I'm wondering if it's possible to get good upwind genoa shape with shrouds so outboard, close to lifelines.

Well, you got what you got and it ain't that bad, I think. Some folks sheet their main and genoa in super close and tight and think they have improved their pointing but they may just be getting blown sideways as much as forward. You need to have increased boat speed and thus apparent wind angle improvement to get what you are asking for. With a lower cut genoa and folding prop, get all the extraneous weight off the boat except for the friends on the windward rail, that will help with the increase in speed and ability to sheet in closer, but, yes, your shrouds are out a bit farther than a boat more designed for racing... but it is still a boat with pretty respectable performance, no?
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Old 18-09-2016, 15:31   #35
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Re: S2 9.2A Poor Pointing Ability ??

You can figure out your sheeting angle using simple geometry, so that you have a number which you can compare to some other boats. Though you can also get pretty close by just using the offset from centerline of your jib tracks/leads, & how far aft of the bow the sheet is led. You can use the number when talking to a local expert, or sailmaker too.

There's info on sail & rig tuning which often can be downloaded from sailmaker's websites, plus at www.L-36.com, etc. And this book's been out for a while, but it's still a good one, with nice instructions, pics, & examples in it.
Sail & Rig Tuning by Ivar Deckham https://www.amazon.com/Sail-Rig-Tuni...g+ivar+deckham

As to how tightly to sheet in the jib, much of it depends upon wind speed, as well as on sea state. Since if it's choppy you won't be able to sail so close to the wind, with the waves bouncing the wind out of the sails, & diminishing boat speed. So that it's necessary to keep the sails more fully powered up to accelerate up to speed after each knock.

When it's light, you have to foot a bit more, as you're not moving fast enough to generate as much lift from your underwater foils in order to cut your leeway, particularly the leeway which happens when you try & sail too closely to the wind.

For a reference for your jib trimmers, put a pair of bands on your spreaders, made from electrical tape or similar, at 6" in from their ends, & 12". That way your they have a fixed "ruler" by which to accurately gauge how close the jib is to them.

Hope that helps
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Old 21-09-2016, 21:01   #36
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Re: S2 9.2A Poor Pointing Ability ??

Gentlemen, here's a good graphic which explains, more than anything I believe,
the boat's difficulty in pointing high. Unfortunately I don't see a way around it.

Caliber Yacht Inboard Genoa Tracks and Chainplates

It's just not going to compete with most racer/cruisers better equipped for racing, upwind at least. It's a fun boat to sail nonetheless, even single-handed.
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Old 21-09-2016, 22:00   #37
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Re: S2 9.2A Poor Pointing Ability ??

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Originally Posted by JIvories View Post
Gentlemen, here's a good graphic which explains, more than anything I believe,
the boat's difficulty in pointing high. Unfortunately I don't see a way around it.

Caliber Yacht Inboard Genoa Tracks and Chainplates

It's just not going to compete with most racer/cruisers better equipped for racing, upwind at least. It's a fun boat to sail nonetheless, even single-handed.
However, this (and all other design factors) is all taken into account in the PHRF rating assigned to the boat... so in that sense you can indeed compete with the r/c boats... at least on corrected time.

Jim
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