Reefpoints on the Jib

[Sailor_Grant]

My roller furling genoa has circles stitched onto the sails that I assume are marking the reef points.

What are these circles and how should they be used/positioned?

There is a piece of foam at the beginning of the luff that I assume helps with reefing, do the circles mark where to put the sail to properly have the foam on the roller furler, or are they more of a guide to show you where to adjust your jib cars etc.

[psk125]

We had reefing cringles on a Solent jib on a boat I sailed aboard. They ran more or less parallel to the foot, and the sail had bigger grommets sewn in for the reefed tack and sheeting points. Reefing it lowered the center of effort of the sail and reduced the area by about a third. It was useful in winds from 30 to 40 knots. Once the reef was in we could run sail ties through a cringle or two to tie up the loose bunt of the sail. On a roller-furling genoa, reefing points would not seem needed. Cringles might be used to tie up the bunt of the sail if, unrolled, it was catching waves or if the helmsman needed to see better.

[Jim Cate]

Yes, the circles are only guides to show roughly how much sail you have rolled up. They can be useful if you note the proper sheet lead positions for each spot and point of sail.

Jim

[fxykty]

Originally Posted by Jim Cate

Yes, the circles are only guides to show roughly how much sail you have rolled up. They can be useful if you note the proper sheet lead positions for each spot and point of sail.

Jim

Hopefully the OP’s furling sail was properly designed (possibly so, given the foam luff) so that the same sheet lead can be used regardless of how much or little the sail is furled.

For the OP, yes, the little circles, of places at intervals along the foot, indicate the position of each reef’s tack - i.e. how much to furl the sail for each reef point. We marked our jib ourselves to show the three reef points (70% area, 50% area, 20% area).

[Jim Cate]

Originally Posted by fxykty

Hopefully the OP’s furling sail was properly designed (possibly so, given the foam luff) so that the same sheet lead can be used regardless of how much or little the sail is furled.

For the OP, yes, the little circles, of places at intervals along the foot, indicate the position of each reef’s tack - i.e. how much to furl the sail for each reef point. We marked our jib ourselves to show the three reef points (70% area, 50% area, 20% area).
Attachment 223052

With respect, he said the sail was a genoa, and most genoas are not designed so that the lead does not move as the sail is reefed. Yankee type sails, ones with very high clews, can approach that performance, but IME, not genoas with big overlaps a nd relatively low clews.

Jim

[Quebramar]

On my 140 genoa, the sailmaker put 2 marks in order to provide references and also to avoid reefing too much. They had put additional canvas layers up to the 2nd mark in order to strengthen the foot for stronger winds. Reefing beyond the 2nd mark would make the sail more vulnerable and could damage it.

[fxykty]

Originally Posted by Jim Cate

With respect, he said the sail was a genoa, and most genoas are not designed so that the lead does not move as the sail is reefed. Yankee type sails, ones with very high clews, can approach that performance, but IME, not genoas with big overlaps a nd relatively low clews.



Jim

Oh, my mistake, I was extrapolating too much from our high aspect ratio self-tacking jib.

For a cutter rig it would make sense to have a big overlapping yankee style genoa so as to benefit from not having to move the sheet lead for the first reef. Then the staysail takes over for higher wind speeds and removes the need to deep reef the genoa.

[cal40john]

Originally Posted by fxykty

Hopefully the OP’s furling sail was properly designed (possibly so, given the foam luff) so that the same sheet lead can be used regardless of how much or little the sail is furled.

For the OP, yes, the little circles, of places at intervals along the foot, indicate the position of each reef’s tack - i.e. how much to furl the sail for each reef point. We marked our jib ourselves to show the three reef points (70% area, 50% area, 20% area).
Attachment 223052

The foam luff is to take up more sailcloth in the middle of the luff as it is rolled. This is to keep the sail from taking on a deep draft shape when reefed.

[meirriba]

You can find reefing points by yourself.
Start with full sails in nice wind (15 kn?).
See that your boat is properly balanced, usually it would have a slight weather helm, like 5-7 degrees or whatever you believe is good for you.
Now take the mainsail down to 1st reef.
The boat will have lee helm. Start rolling the genoa/jib, while monitoring helm until you get to the point where helm gets back to the original weather helm feeling. You may need to adjust also the car position a little forward (but remember that tight foot is better in a blow as it opens the leech).
Mark sail and car positions for 1st reef.
Repeat the process for 2nd and 3rd reef if mainsail.
Those will be the precise reefing points for the genoa/jib, as not guesswork but balanced boat.
It is also a nice sail set exercise/pastime��

[fxykty]

Originally Posted by meirriba

You can find reefing points by yourself.
Start with full sails in nice wind (15 kn?).
See that your boat is properly balanced, usually it would have a slight weather helm, like 5-7 degrees or whatever you believe is good for you.
Now take the mainsail down to 1st reef.
The boat will have lee helm. Start rolling the genoa/jib, while monitoring helm until you get to the point where helm gets back to the original weather helm feeling. You may need to adjust also the car position a little forward (but remember that tight foot is better in a blow as it opens the leech).
Mark sail and car positions for 1st reef.
Repeat the process for 2nd and 3rd reef if mainsail.
Those will be the precise reefing points for the genoa/jib, as not guesswork but balanced boat.
It is also a nice sail set exercise/pastime��

Not all reefing charts have headsail and mainsail reefs in lockstep. A large genoa may need to be reefed before the first reef, while a smaller jib may be full when the main needs to be first reefed.

Reefing should also be sufficient to reduce power relative to the wind so the boat is not overpowered: that may be more or less than that required to balance the boat.

I’m also not sure that a boat can remain balanced when deeply reefed via a furling headsail as the overall centre of effort (as will each individual sail’s centre of effort) will have moved forward. As the keel doesn’t move, the boat must develop lee helm.

Otherwise, this is a good exercise for developing a good feel for your boat’s balance.

NB, weather helm as described above applies to most monohulls but does not apply to multihulls. It is the heeled waterline that causes a natural weather helm and that of course does not apply to multihulls.

[meirriba]

Originally Posted by fxykty

Not all reefing charts have headsail and mainsail reefs in lockstep. A large genoa may need to be reefed before the first reef, while a smaller jib may be full when the main needs to be first reefed.

Reefing should also be sufficient to reduce power relative to the wind so the boat is not overpowered: that may be more or less than that required to balance the boat.

I’m also not sure that a boat can remain balanced when deeply reefed via a furling headsail as the overall centre of effort (as will each individual sail’s centre of effort) will have moved forward. As the keel doesn’t move, the boat must develop lee helm.

Otherwise, this is a good exercise for developing a good feel for your boat’s balance.

NB, weather helm as described above applies to most monohulls but does not apply to multihulls. It is the heeled waterline that causes a natural weather helm and that of course does not apply to multihulls.

I agree with almist all written above. To add:
The suggested procedure will find where to put reefing marks on the sail. Then, in an actual situation, as you heve pointed out, the reefing chart of the builder may suggest the order if reefing, using this particular points.
Of course, you may also reef the forward sail to measures inbetween the marks if you think adequate for specific situation.
As to cat vs. mono, I have assumed that the OP means a mono, a catamaran is a different animal (being a cat?&#129300.
The only point about I wish to differ is a non-balanced boat while reducing power. I would like to have a balanced boat always.