Flattening the sail when reefing...

[T37Chef]

Here goes,

As I am learning more and more about reefing techniques, yesterday I wanted to try and get the foot of the sail flatter to spill more wind. I had let the traveler to leeward a bit but as I looked at the foot, I thought perhaps moving the sheave more aft would/should act more like the out haul.

My question is: For the reefing line, how far aft should the sheave be to the reefing cringle?

Maybe this is a stupid irrelevant question, don't know, but should I be doing something else entirely?

BTW...I do not have a back-stay tensioner, both the halyard and boom vang were taught?

Please correct me if I used improper terminology

Thanks,

[tenuki]

I would imagine you would want the reefing line to point midway up the mainsail luff when tight, similar to how setting a jib car correctly works but I bet the experts here have some formula. That is roughly how mine is set up and it works well.

I sometimes use the second reefing point to rig a makeshift cunningham, it's ugly but it sort of works, your mileage my vary. I'm sure everyone here will tell me how wrong that is. lol.

[sailingdog]

IMHO, the sheave should be slightly aft (three-to-six inches) of the reefing cringle. The sail's reefed clew needs to be pulled both down to the boom and aft. If you have the sheave directly below the cringle, you get the down, but very little aft tension.

Of course, if you have a very large sail, the distance aft of the cringle it has to be must increase, since the sail will stretch more...

Ideally, the reefing line should be almost flat when the sail is reefed...since it should have the cringle nearly snugged up against the boom.

[Lancer28]

All three of mine measure 1/2 the distance from each reef point's cringle to the end of the boom.

Hope that helps.

Yes, tightening them spills a lot of air. The more knife-edge you can get the sail, the better. I am actually thinking about adding something like a block system before the reef cleat to gather a tad more purcahse, because sometimes I cannot get the sail as tight as I wanted. Ahhh - all in the "to-do" box.

[sailingdog]

IMHO, that would be overkill, especially if the reefs are fairly deep or on the second reef..where there isn't as much sail material to stretch out.

Originally Posted by Lancer28

All three of mine measure 1/2 the distance from each reef point's cringle to the end of the boom.

Hope that helps.

Yes, tightening them spills a lot of air. The more knife-edge you can get the sail, the better. I am actually thinking about adding something like a block system before the reef cleat to gather a tad more purcahse, because sometimes I cannot get the sail as tight as I wanted. Ahhh - all in the "to-do" box.

[T37Chef]

Thanks Dog, that distance makes more sense to me.

I have two reef lines rigged, one on each side of the sail, and if I need to reef a third time I would use the first reef line re-routed. Anyway there is a sheave on the port side of the boom, I thought, set for the second reef cringle, and what I have been using, but it is almost directly under that reef point, so I am not getting the pull aft on the foot as needed. Looks like I either need to move it aft or put it on a track like the starboard reefing sheave.

Thoughts?

[Hartley18]

Nearly every boat I've been on has a different set-up, but by the sound of it you will certainly need to move the sheave aft. Perhaps it's a newer mainsail?

Many production yachts have a triple-sheave at the end of the boom (reef lines port & starboard and the outhaul in the middle) which means less holes in the side of your boom. Could you do this instead?

I suppose the flip-side to your question is: Can the reefing sheaves be too far aft??

[SEMIJim]

Originally Posted by Hartley18

I suppose the flip-side to your question is: Can the reefing sheaves be too far aft??

The further aft your reefing sheaves, the harder it is to get the reef point down tight to the boom. We had this problem when running reefed a couple weekends ago--leaving our main way too full. Solution (we'll have to try this next season, now): Another line through the reef point to pull it straight down. Sailor who told me of this trick uses a piece of webbing with Velcro on it. Gets the reef point right down snug on the boom, that way, and it's easy to take loose.

Jim

[Hartley18]

Originally Posted by SEMIJim

The further aft your reefing sheaves, the harder it is to get the reef point down tight to the boom. We had this problem when running reefed a couple weekends ago--leaving our main way too full. Solution (we'll have to try this next season, now): Another line through the reef point to pull it straight down. Sailor who told me of this trick uses a piece of webbing with Velcro on it. Gets the reef point right down snug on the boom, that way, and it's easy to take loose.

Jim

Thanks, Jim - I had always wondered about that.

I've just converted our main to loose-footed and the same suggestion about webbing/velcro was made to me. It works great for the outhaul, but my only hesitation using this set-up for reefing would be that you'd have to mess around near the end of the boom in a half-gale (the reason you're reefing, right?) with a 1' length of webbing in one hand, trying to free the velcro with the other... not a good thing if you can help it.

Apologies to the Chef for hijacking his thread...

[Tartan34C]

When I laid out the hardware for reefing on the boom I always set it up so that the aft face of the turning block for the reef outhaul was on a 45 degree angle to the cringle when it was at the boom. If possible I would mount the block on a track so it could be adjusted but if it was to be fixed I used the 45 degree rule.
All the best,
Robert Gainer