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Old 03-01-2021, 21:19   #16
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Re: Sail trim question

Whilst I dont know your boat 5mph of wind is not much. I'd say you dont want the sails too flat i.e. not too much halyard, sheet or outhaul tension.
Sit to leeward as a little heel will help the sail shape.
Have you got jib car all the way aft?

You need to get some forward speed to be able to go to windward in that little wind so dont suddenly point high out of tacks, you can come up slowly into the wind as the speed rises.

Mph is not the same as knots, google that.
Agree with oher posters, read some books if you cant get anybody to teach you.
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Old 03-01-2021, 22:21   #17
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Re: Sail trim question

Quote: "I think I am letting my headsail get too big. "

Yes, I think this has been your principal problem. A roller furling jib confuses many novices. For now, think of it having only three positions: 1) big enuff to just reach to the position of the mast. That is your "working jib"; 2) Bigger than that, rolled all the way out. That is your "genoa jib" ("genny"); 3) rolled out only about half the distance from forestay to mast. That is your "storm jib".

Now think of the centerboard sticking down as if it were a hinge pin. As the boat changes heading it does so by rotating about the hinge pin. Now think about this hinge pin rising up, conceptually, all the way to the top of the mast.

If you handle your sails so that the "Centre of Effort" (the point where the combined force of the wind in the sails may be conceived as acting) falls AFT of (behind) the hinge, the boat will head up into the wind. You can negate that tendency by pulling the tiller to the side the wind comes from, i.e. "the weather side". When you need to do that to make the boat hold its course without turning, the boat is said to have "weather helm".

If you handle your sails so the Centre of Effort ("CE") falls FORWARD of the "hinge line" the boat will turn way from the wind. You can negate that tendency by pushing your tiller to the side AWAY from the side the wind comes from, i.e. the "lee side". When that is required for the boat to hold its course, the boat is said to have "lee helm".

Your FIRST job in trimming sail is to make the area of sail forward of the hinge line and the area of sail aft of the hinge line such that the boat "balances" because the CE falls ON the hinge line. Then the boat will hold its course even when you let go the tiller. and that is what you want.

On the Cat 22 the proper way to do that is to adjust the area of jib you unfurl but leave the mainsail at it's full area. So get your furling gear fixed :-)

All the above is a bit simplistic and meant only to familiarize you with the basic concept of "balance" and how it affects the helm - whether you will have "weather helm" or "lee helm".

Get that under your belt, then tomorrow (it's 2200 hrs here) we can carry on with some more sophisticated stuff building on what I've said above.

So hang in there - we'll get your "problem" solved :-)

Cheers

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Old 03-01-2021, 22:37   #18
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Re: Sail trim question

on my old C-22 (hull 61) the traveler was a short device mounted at the transom. It offered rather little range of adjustment and thus was not as important a trim tool as on some other boats.

When I was racing on SF bay in it, we used working jibs rather than genoas in the SYRA Cat 22 fleet, and I had a reef in the mainsail much of the time in afternoon races. It sounds like you may have been somewhat overpowered if your jib is an overlapping genoa. Fixing that furling line should be an immediate task IMO. Even better, a non-overlapping jib that you use on strong wind days (like most summer days on the bay), for a roller-reefed genoa is a poor sail for windward work.

The C-22 does develop weather helm when heeled very much, so it is important to sail her fairly flat. Putting the traveler down all the way is a start, followed by easing the main sheet to take heel off, even to the point of luffing a bit. With a properly sized jib I'd keep it sheeted in till the leech was just off the spreader tip. If the helm was still much to windward then heading up a few degrees until the heel came off was the next step. With some practice one learns to feather it upwind, balancing between loosing boat speed and excessive heel angle (and associated leeway). Another stronger wind tip is to move the jib fairlead aft somewhat from it's normal position. This allows the top of the jib to twist off a bit which also helps reduce heel angle.

These techniques are not unique to the C-22, but hold for most smaller yachts, and spending some time reading any of the sail trim books will not only suggest other techniques, but explain why they (and the above) work.

To me, this sort of experimentation was really fun and added much to both the sailing skills and the enjoyment of sailing in general. And they work in larger boats, too, with appropriate scaling factors.

Go sailing, have fun and learn the skills... pretty damn rewarding IMO!

Jim
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Old 03-01-2021, 22:37   #19
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Re: Sail trim question

Quote:
Originally Posted by laanan View Post
* It was very light air the past couple times I have sailed. Lucky to get 5mph (sub question, when the Sailflow app or wind speed on Google says mph, is that equal to knots? So 5mph = 5 knots). I know knots are not quite the same as land miles when measured, but how does that relate to knots vs mph for wind speed???


* I think I am letting my headsail get too big.

In winds that light, you want all the sail you can get out.


Also, you don't want to crank anything on hard, you need lots of shape in your sails. Ease the halyard, backstay and outhaul and use the traveler, not the mainsheet to get the boom on the centreline when close hauled (i.e. have the traveler car well to windward and ease the mainsheet).
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Old 04-01-2021, 04:46   #20
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Re: Sail trim question

Quote:
Originally Posted by Jim Cate View Post
on my old C-22 (hull 61) the traveler was a short device mounted at the transom. It offered rather little range of adjustment and thus was not as important a trim tool as on some other boats.

When I was racing on SF bay in it, we used working jibs rather than genoas in the SYRA Cat 22 fleet, and I had a reef in the mainsail much of the time in afternoon races. It sounds like you may have been somewhat overpowered if your jib is an overlapping genoa. Fixing that furling line should be an immediate task IMO. Even better, a non-overlapping jib that you use on strong wind days (like most summer days on the bay), for a roller-reefed genoa is a poor sail for windward work.

The C-22 does develop weather helm when heeled very much, so it is important to sail her fairly flat. Putting the traveler down all the way is a start, followed by easing the main sheet to take heel off, even to the point of luffing a bit. With a properly sized jib I'd keep it sheeted in till the leech was just off the spreader tip. If the helm was still much to windward then heading up a few degrees until the heel came off was the next step. With some practice one learns to feather it upwind, balancing between loosing boat speed and excessive heel angle (and associated leeway). Another stronger wind tip is to move the jib fairlead aft somewhat from it's normal position. This allows the top of the jib to twist off a bit which also helps reduce heel angle.

These techniques are not unique to the C-22, but hold for most smaller yachts, and spending some time reading any of the sail trim books will not only suggest other techniques, but explain why they (and the above) work.

To me, this sort of experimentation was really fun and added much to both the sailing skills and the enjoyment of sailing in general. And they work in larger boats, too, with appropriate scaling factors.

Go sailing, have fun and learn the skills... pretty damn rewarding IMO!

Jim


Ditto!
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Old 04-01-2021, 15:45   #21
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Re: Sail trim question

After only six months you are to be commended for your sailing skills and understanding your boat's responses so well.
Things I'd look at:
1. Age of sails
2. Roller furling headsails are not generally known to help a boat point well
3. Such light air needs sails to be not flat (more camber) to generate lift to drive the boat. Sails that are sheeted in too tight and trimmed to flat do a great job of sailing a boat sideways.
4. The boat going so slowly does not help pointing ability. As boat speed increases then you can trim and point higher. But first you have to get the boat moving forward.
5. 5 knots is 5.75 mph so it's close, kind of. Both are a very light breeze. A lot of bigger boats can barely move in that, let alone point very high.
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Old 04-01-2021, 20:41   #22
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Re: Sail trim question

Quote:
Originally Posted by Don C L View Post
After only six months you are to be commended for your sailing skills and understanding your boat's responses so well.
Things I'd look at:
1. Age of sails
2. Roller furling headsails are not generally known to help a boat point well
3. Such light air needs sails to be not flat (more camber) to generate lift to drive the boat. Sails that are sheeted in too tight and trimmed to flat do a great job of sailing a boat sideways.
4. The boat going so slowly does not help pointing ability. As boat speed increases then you can trim and point higher. But first you have to get the boat moving forward.
5. 5 knots is 5.75 mph so it's close, kind of. Both are a very light breeze. A lot of bigger boats can barely move in that, let alone point very high.
^ all this.
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Old 05-01-2021, 09:28   #23
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Re: Sail trim question

Generally speaking you want the mast raked aft a bit, not forward. As a rule of thumb,if the end of main halyard hanging loose lies an inch or two from the mast at boom height that’s a good start for general sailing. You would only rake the mast forward to relieve excessive weather helm. It doesn’t sound like you’ve got that. You would be heaving on the tiller to keep the boat in line in moderate winds. Gentle weather helm is often designed in and gives the helm some ‘feel’. A completely neutral helm feels dead. Many, not all, boats can be balanced to sail themselves for a short time even if they have inherent wether helm. The next step, if you want to leave the helm is to balance the boat as best you can, then lash the tiller. Elastic is sometimes used for this. Most boats will sail like this for some time. Next step up from that is an autopilot.
Top racing boats often have hydraulic rams to change mast rake on the fly but most boats don’t.
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