In boom reefing padeye positioning

[sanibel sailor]

I switched from end of boom sheeting to midboom on my Bristol 35.5 and the boom took on a bend, so I am replacing it with a newer and bigger boom from a Catalina 400. I have always had external reeflines running along the boom. This new one has the lines running inside the boom, no surface fittings and 4 sheaves at each end with cam style grippers on two of them at the gooseneck. One will be for the outhaul, one for topping lift vs spare (perhaps to serve as a third reef eventually), and two for reeflines.

I am getting ready to install the padeyes in the groove at the bottom of the new boom. There will be one for the vang and three for the mainsheet tackle which will match my old positions.

I am puzzled by the reef padeye positioning.

Looking at the Sparcraft website, it shows the padeyes for the dead end of the reeflines forward of where the reef grommet is located. This would just pull the sail straight down. I have always seen (on external systems) the padeye aft of the cringle so it pulls the sail down and back, tensioning the foot and flattening the sail. I have always seemed to get much better results by pulling the reef line tight as possible, but the turning block has been directly opposite the padeye on the other side of the boom, not at the aft end.

I tried googling it and got a zillion pages of in-boom furling...

[UNCIVILIZED]

Hold up for a minute, before you go & break out the power tools. Both in terms of sheeting attachments, reefing line ends, as well as the vang.

On your sheeting attachments, is there any substantial reason why you can't just run a Spectra strop/Loup around the boom for each block? It works for thousands of other boats, including pretty much every high dollar race boat out there. And is cheap, strong, reliable, plus it doesn't require drilling holes in things (creating stress risers). It needn't even be a Loup proper, Spectra's strong enough that odds are you could get away with tying them on in a manner akin to Spectra turnbuckles.

Ditto on attaching the bitter ends of your clew reefing lines to the new boom. With a few exceptions, I've always just tied them around the circumference of the boom. The bonus side of which, is that you can fine tune their position to match what the sail likes the best. And when it's time for a new main, if the reefs are spaced differently, then you have the freedom to move the bitter end's position's to mate up with it. Plus, no holes in the boom, & less $ spent on hardware.

I think that what you're seeing on the Sparcraft site, IS the bitter ends of the reefing lines pretty much vertically in line with the clew grommets in the sail. This is because, with the running (moveable) part of the clew reefing line being led through the boom's aft end (over the sheaves), the two parts differing angles combine to pull the reef BOTH aft & downwards.

Do yourself a favor, & try it out as suggested above first. Yes, it's definitely different than how things are setup on boom's with external reefing systems. But it works fine. And based on your description of your new boom, it's how it's designed to be rigged.

On the vang, are you looking to attach a padeye for a soft vang, or a rigid one? If the former, odds are you'd be better served by a 2" (50mm) wide strap, fitted with D-rings sewn to each end (or the idea below might serve you even better). And the strap works in the same manner as a Spectra Loup used to attach a mainsheet, or mainsheet block to the boom.

However, in a pinch, a Spectra Loup/pennant would probably work here too. It's just that with a wide strap, the load from the vang is spread out over more surface area. And loads on vangs tend to run higher than other attachments to the boom, due to the geometry of their attachment.

Some of the boats which I've crewed on, & or looked after, even went so far as to have a 6"-9" wide strap of (Kevlar or Spectra) cloth, with a fan pattern of Spectra sewn to it, leading to the D-rings. And said "strap" was then draped over the boom, & connected to the vang.
It's purpose being, to spread out the load from the vang over an even wider span of the boom. Despite the boom having extra reinforcement in this area.

This high load is why on a lot of booms, you'll see "doublers" aka extra reinforcement built into/welded onto the boom in the vicinity of where the vang's attached. And even with this (doubler) booms most often get bent or broken either at the vang attachment point (a hard "nose"), or at the aft most end of the doubler. The loads can run that high (MUCH higher than the sheet).
Sometimes this happens because someone eases the main sheet a lot, but forgets to loosen the vang. And without the sheet assisting in holding the boom down, then most of that vertical load gets transferred to the vang... and bang, expensive goof/destroyed boom.

So on this too, it might be wise to temporarily hold off on mounting anything, until a clearer picture of the situation is known.

[sanibel sailor]

OK, I will consider the strops for the reefs.

Too late on the vang attachment which is already mounted- an extended SS plate for my block and tackle system. I am not too worried about it, as the new boom looks twice as stiff as the old. Similarly the mainsheet padeyes are mounted also.

NOW... If I go with strops, how are they secured to keep them from sliding forward and aft?

[roverhi]

If I had to do it again, would just tie a bowline around the boom for the ends of the clew reefing lines. That would be a couple less holes in the boom and allow the clew line to float to it's natural best position depending on how flat you want the sail.

[jmschmidt]

You’ve discovered that boom-end reefing tackle installed on many new boats for several years doesn’t make much sense. The primary function of a reefing system should be to flatten the sail. The secondary, but also necessary, function is to shorten the sail. What good does it do to shorten the sail and still leave a big bag in it at the foot?

Both the reefing line deadeye pad-eye and a cheek block should be placed in the same position on either side of the boom somewhere aft of were the sail reefing grommet will be when the sail is shorten and the foot is stretched tight. You have to play with this at the dock to get the angle from the pad-eye and cheek to the grommet just right. This minimizes the effect of line stretch under tension. The line is then run from the pad-eye forward to the sails reefing point grommet and back to the cheek block. The line can then be run externally or internally to the mast end of the boom where it is winched tight and secured. To accomplish this I’ve cut a slot in the side of boom just forward of the cheek block to run the line internally to a double clutch installed inside the boom. The levers of the clutch extend below the boom through another slot cut in the bottom of the boom at its forward end. The lines then run through two sets of blocks and end up on the deck where a two-speed reefing winch is mounted. I have a half inch stainless steel rod shaped like a bulls horns at the gooseneck which takes the luff reefing grommet. The system is easily operated on either tack. I have a two-reef setup, three would get a little crowded inside the boom but doable with an oval shaped boom with the wider dimension oriented to the horizontal.

I’ve read a couple of other ideas posted and I must tell you I have a boom that was made in 1969 and survived that year’s TransPac to became the Hawaii Yacht Racing Assn. points champion in 1970 and 71. It’s built like the barrel of a M1A1 Abrams Tank and just about as heavy. I have little fear of drilling holes and cutting slots where ever they need to go. This new stuff however? I’m not so sure.

[roverhi]

A clarification. My boom is a newish internal reefing boom. The clew reefing lines exit the aft end of the boom, go through the sail clew cringle and back to the boom. By tieing the bitter end of the clew reefing line around the boom, you can adjust the draft of the sail infinitiely as you aren't restricted by where a padeye on the boom is located. The more you crank on the clew reefing line, the flatter the sail. Works a treat. The clew reefing lines going forward run inside the boom dumping out via sheaves on the bottom of the goose neck casting where they are led back to the cockpit on my boat.

[Jim Cate]

You’ve discovered that boom-end reefing tackle installed on many new boats for several years doesn’t make much sense. The primary function of a reefing system should be to flatten the sail. The secondary, but also necessary, function is to shorten the sail. What good does it do to shorten the sail and still leave a big bag in it at the foot?

Doesn't make much sense??

Don't know if you have ever used a "boom-end" reefing system, but I have... for nearly thirty years now on two boats and four booms. My experience is that it works quite well, and certainly does a good job of flattening the reefed sail.

NEarly every rig designed in the past twenty years has used this system, and I've not seen all that many boats with poorly reefed sails. I believe that you are misguided in your advice to the OP.

Jim

[um saudade]

Everybody has a different take on all of this. I use a jiffy reef set-up with three reef points and three lines led to the base of the mast. I carry a main with four reefing points total as I don’t carry a trysail by rely on the last reef point in the main to make a balanced pair with the staysail.
　
　
I was taught that the jiffy reef is not to be used for sailing but rather to reef only. Once I have the main shortened and the excitement is over I then use a small block set with a cunningham hook to adjust the foot tension(an outhaul, in effect), tensioning to the clew end of the boom and then release the tension on the jiffy reef.

I have seen the chafe at the cringle eat the jiffy reef line in a short time and then some time when you need it the most, it parts and you have no easy way to reef at all. Also, by using a separate outhaul on the new clew it is not so important as to where the block is in relationship to the cringle in the sail, as all it takes is to have the block point somewhat close to depower the main, which is the most important issue. Take into consideration the loose sail you are tying up with the gaskets too, because that really starts changing the geometry as you go to reef # 2 and #3. Fine tuning can come later with the separate outhaul, get it down and depowered is the first consideration.

I have had a few words with sailmakers and racers on this point as racers don’t want extra gear to fuss with but I think as a cruiser I want a system that works well and is dependable over the years. As to getting the turning blocks exactly right the reef clew points, I have seldom seem a main sail reefing point system that was perfect and could not improve a little with some tweaking with the separate outhaul system.

um sadade

[Nicholson58]

Originally Posted by sanibel sailor

I switched from end of boom sheeting to midboom on my Bristol 35.5 and the boom took on a bend, so I am replacing it with a newer and bigger boom from a Catalina 400. I have always had external reeflines running along the boom. This new one has the lines running inside the boom, no surface fittings and 4 sheaves at each end with cam style grippers on two of them at the gooseneck. One will be for the outhaul, one for topping lift vs spare (perhaps to serve as a third reef eventually), and two for reeflines.

I am getting ready to install the padeyes in the groove at the bottom of the new boom. There will be one for the vang and three for the mainsheet tackle which will match my old positions.

I am puzzled by the reef padeye positioning.

Looking at the Sparcraft website, it shows the padeyes for the dead end of the reeflines forward of where the reef grommet is located. This would just pull the sail straight down. I have always seen (on external systems) the padeye aft of the cringle so it pulls the sail down and back, tensioning the foot and flattening the sail. I have always seemed to get much better results by pulling the reef line tight as possible, but the turning block has been directly opposite the padeye on the other side of the boom, not at the aft end.

I tried googling it and got a zillion pages of in-boom furling...

On the Heritage One-Ton I raced we had reefing like you describe. The reef line exited the boom end under one of several pulleys. From there, it went through the reefing cringle and returned to the boom. Naturally, all reef lines (3) originated from the boom end and passed through the cringle from the port or starboard side of the sail. The belay end went to a pad-eye on the boom at the point appropriate to the required sheeting angle. Since each reef cringle is progressively farther forward, each pad eye is likewise more forward. You may best do this in calm at the dock. You could certainly tie around the boom but long-term you will scuff the paint. Also, the loop around the boom may interfere with the outhaul.

As to the sheeting, I suggest you might spread out the blocks to distribute the load on the boom. Also, note on our sheeting the mainsheet originates on starboard; runs in the blocks and exits to a turning block to the cabin winch. This arrangement reduces the impact on a jibe quite a bit.

[sanibel sailor]

I have my mainsheet attached to three widely spaced padeyes, then led forward to the base of the mast, so the boom can be let down with the traveller without adjusting the sheet.

I installed the boom today. I put the end on with machine screws rather than rivets in case I have to pull it one day when the internal spaghetti goes bad as I suspect it will. I have the reef padeyes in the slot, but not secured, and the first reef line bow lined to the boom thru the padeye. I mostly day sail at present and rarely need to reef, but I will give it a test drive here soon.

[UNCIVILIZED]

Originally Posted by Jim Cate

Doesn't make much sense??

Don't know if you have ever used a "boom-end" reefing system, but I have... for nearly thirty years now on two boats and four booms. My experience is that it works quite well, and certainly does a good job of flattening the reefed sail.

NEarly every rig designed in the past twenty years has used this system, and I've not seen all that many boats with poorly reefed sails. I believe that you are misguided in your advice to the OP.

Jim

+1
Ditto on what Jim said. And are you then saying that the couple hundred thousand sea miles, & boats numbering in the triple digits which I've used this type of system on is wrong/inferior? If so then you might want to go & straighten out a very long list of professional sailors whom I know, from the very pinnacle of the sport on down. Ditto on most of the boat builders, sail makers, spar makers, & riggers out there.

External reefing blocks/systems are more of a hold over from when booms weren't hollow, & thus couldn't be set up with internal reefing. And or is popular on boats with booms too small to accommodate the necessary hardware to reef this way.
Externally mounted jiffy/slab reefing came about as an improvement to roller reefing. And it does work, to varying degrees. Albeit, it's rather structurally impractical & inefficient on larger yachts. In addition to creating more windage/drag. As well as that it's hardware can be problematic for the reefed portion of the main hanging down to chafe upon.

Plus, I, personally, am not a fan of the tattoo which external reefing lines create as they beat on the boom in any sort of wind. Nor said effect, long term, of that on a boom's finish. Although this system seems popular mostly on unfinished booms, on boats from the 60's & 70's.

[olaf hart]

Originally Posted by Jim Cate

Doesn't make much sense??

Don't know if you have ever used a "boom-end" reefing system, but I have... for nearly thirty years now on two boats and four booms. My experience is that it works quite well, and certainly does a good job of flattening the reefed sail.

NEarly every rig designed in the past twenty years has used this system, and I've not seen all that many boats with poorly reefed sails. I believe that you are misguided in your advice to the OP.

Jim

Welcome back to Kettering Jim.

I think the poster is commenting on the outhaul function of a reef, I notice my in boom reefing doesn't flatten the foot of the sail as much as I would like.

Do you have any suggestions on foot tension?

[roverhi]

Originally Posted by olaf hart

Welcome back to Kettering Jim.

I think the poster is commenting on the outhaul function of a reef, I notice my in boom reefing doesn't flatten the foot of the sail as much as I would like.

Do you have any suggestions on foot tension?

If your In boom reefing is not providing enough force to flatten the sail either the dead end pad eye on the clew reefing line is too far forward or, if the bitter end is tied around boom, you need a winch to apply enough tension to the clew reef line to pull the sail flatter.

[donradcliffe]

Every time I've set up the slab reefing with internal lines, I've hoisted the main to the appropriate reef in the front, then tensioned the halyard. The next step is to take the sliding eye for the reef and move it back to where the line from the cringle to the eye goes back and down at a 45 degree angle when the reefing line is moderatly tight--then mark and secure the eye.

As far as reef lines chafing through, if they are lead fairly they should last over 10 years.

[UNCIVILIZED]

Originally Posted by olaf hart

Welcome back to Kettering Jim.

I think the poster is commenting on the outhaul function of a reef, I notice my in boom reefing doesn't flatten the foot of the sail as much as I would like.

Do you have any suggestions on foot tension?

Also, are you making sure to ease the sheet & vang sufficiently when tucking in a reef?

And for a different take on things, if one's dead set on padeyes on the boom for the bitter end of the reefing line, might I suggest mounting a long piece of 1 1/4" jib track onto the side of the boom. And then slip a couple of pin stop padeyes onto the track. Though in going this route, I'd still suggest running the bitter end of the reefing line fully around the boom (as well as through the padeye). This way you still retain some adjustability on where the end of the reefing line is positioned. As opposed to using fixed padeyes.