Slab reefing - how to mount turning block at gooseneck?

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RobbieH

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Hi,

I am updating my slab reefing to run the clew lines back to the cockpit. Tack will still be held down using a hook on the gooseneck.

My boom doesn't have multiple sheaves at the gooseneck (just one for the outhaul). Reefing lines are external to the boom.

What is the best way to turn the reefing lines through 90 degrees to get them down to the mast foot blocks?

I would prefer that all three reefing lines went down to the port side of the mast and thence back to the port organiser and jammers.

Should I fit three cheek blocks on the port side of the boom? Or would it be better to hang a triple block under the boom? Or something else?

How have other people done this with the reefing lines running external to the boom?

Not wild about the idea of single line for clew and tack by the way ...
 
Not sure if you mean single line jiffy reefing with the lines acting on the luffs as well, or just clew lines.

For the latter I'd use 3 seperate blocks riveted to the boom, staggered just enough for the lines to clear each other; may be necessary to rivet the blocks to shaped alloy plates first, then rivet those to the boom, but there are loads of suitable blocks nowadays.

If at all possible use ball bearing blocks everywhere on the reefing lines, makes a huge difference.
 
Barton used to sell a handy length of "tracking" with some turning blocks on it. You could screw / bolt / rivet it to the boom and then slide each block along it to a convenient position. That would get the lines turned to run paralell to the boom, along towards the gooseneck, I guess.
 
Seajet said:
Not sure if you mean single line jiffy reefing with the lines acting on the luffs as well, or just clew lines.

For the latter I'd use 3 seperate blocks riveted to the boom, staggered just enough for the lines to clear each other; may be necessary to rivet the blocks to shaped alloy plates first, then rivet those to the boom, but there are loads of suitable blocks nowadays.

If at all possible use ball bearing blocks everywhere on the reefing lines, makes a huge difference.
Click to expand...

I mean I want no line on the tack (cringle goes directly on hooks on gooseneck). Just a line up from the boom to the clew, back down to a turning block and along the boom to the gooseneck where the line turns 90 degrees to drop down to the mastfoot. Good point about ballbearing blocks, I have plain blocks for the halyards but for the reefing gear I guess the loads are not so high and don't concentrate in one place on the block (reason no to use ballbearing blocks for halyards). Plus reefing blocks are not in use 24/7 (unlike halyards).
 
Avocet said:
Barton used to sell a handy length of "tracking" with some turning blocks on it. You could screw / bolt / rivet it to the boom and then slide each block along it to a convenient position. That would get the lines turned to run paralell to the boom, along towards the gooseneck, I guess.
Click to expand...

That part I have sorted (aft end of boom). It's how to people rig the turning block to get from the gooseneck down to the mastfoot that I'm thinking about.

I'm thinking that the advantage of the Selden style internal reefing lines with three/four sheaves at the gooseneck is that they swing in a relatively constant arc so not much variation in the amount of line used as the boom swings from across the boat. As I move the blocks aft on the boom (staggered solution) that variation increases. Which might affect clew tension. Haven't got the mast back in the boat yet (should be afloat and mast stepped next week) so I may need to play with the angles once everything is rigged again.
 
Without knowing the boat, size, or specific gooseneck arrangement....


Mast band or mast groove attachment to which to shackle single turning locks?

So long as the axis of each turning block aligns quite closely with that of the gooseneck, and there is a bit of articulation (provided by the shackles) then clew tension should not vary much nor restrict the booms movement.

Why not have a play first, by lashing a couple of blocks in place using line round the mast at gooseneck height perhaps, before committing funds and drilling holes....and verify the geometry..
Or bite the bullet and buy new boom/ end fittings with internal sheaves.(gulp£).
 
I have a solid timber boom, so the reefing pendants run outside it. I have one on each side, which seems easier to arrange to me than three on the same side (I only have two reefs to worry about). I just have cheek blocks on the sides of the boom, as near the end as possible, and the lines run down to ordinary blocks shackled to the tabernacle. There are fairleads in several places along the boom to hold the pendants in place when they're slack; otherwise you'll have a great loop of line hanging down to catch on things (if you tighten it up enough to avoid that you'll pull the sail out of shape).

Have you thought about how you'll actually work a system with the tacks on ram's horns and the clews in the cockpit? Where's the halyard - cockpit or mast? These are the three things you need to put in a reef, and they should all be in the same place. Otherwise you have to move about to complete the procedure (worst combination is tack hooks and cockpit halyard) and it all takes longer. Everything at the mast is fine, everything in the cockpit is fine, a mixture is a pain in the bum unless you always sail with multiple crew so you're never on watch alone.

I share your scepticism at single-line reefing setups, by the way. The alternative is separate tack pendants that run from the tack cringle, via a ring at the gooseneck, down to a block and then aft. You haul down the tack against the halyard, cleat the tack pendant, take up the slack on the halyard, then take in the clew pendant. Job done. This is what I have, and like it. Only downside is that you'd need a lot of deck blocks and jammers on a boat with three reefs, but if she was set up for racing and you don't, you probably have spare ways anyway.

Pete
 
Blueboatman said:
Without knowing the boat, size, or specific gooseneck arrangement....


Mast band or mast groove attachment to which to shackle single turning locks?

So long as the axis of each turning block aligns quite closely with that of the gooseneck, and there is a bit of articulation (provided by the shackles) then clew tension should not vary much nor restrict the booms movement.

Why not have a play first, by lashing a couple of blocks in place using line round the mast at gooseneck height perhaps, before committing funds and drilling holes....and verify the geometry..
Or bite the bullet and buy new boom/ end fittings with internal sheaves.(gulp£).
Click to expand...

Mast groove. As soon as the mast is stepped I'll have a play with some blocks


Can't find boom ends to fit the boom anywhere :( Might go for a new boom next year as it would be nice to run the reefing lines internally.
 
prv said:
...

Have you thought about how you'll actually work a system with the tacks on ram's horns and the clews in the cockpit? Where's the halyard - cockpit or mast? These are the three things you need to put in a reef, and they should all be in the same place. Otherwise you have to move about to complete the procedure (worst combination is tack hooks and cockpit halyard) and it all takes longer. Everything at the mast is fine, everything in the cockpit is fine, a mixture is a pain in the bum unless you always sail with multiple crew so you're never on watch alone.

Pete
Click to expand...

The idea was to use the cockpit lines for quick reefing when I have crew and to be able to adjust halyards and outhauls for tuning from the cockpit. Someone at the mast hooking the tack, someone in the cockpit managing the halyard and grinding in the clew. I've left the existing winch and three jammers on the boom so if I am single handling and find it too painful to have tack at the mast but halyard and clew in cockpit I can quickly revert to doing it all at the mast. The halyards (genoa and main) are run aft to the cockpit (20st winch either side of main hatch servicing the jammers) but I have left the halyard winches on the mast so they too can be reverted to be handled at the mast.

If it doesn't work out I could convert everything to cockpit reefing using pendants on the tacks as well as clews as you suggest. I've got 5 organisers and jammers (plus a clamcleat for parking a lightly loaded line) on either side of the hatch so it gives me a few options. But with three reefs plus outhaul, cunningham and halyard if I use tack pendants that's 9 jammers gone already :eek: and there's still the genoa halyard, staysail halyard, kicker, spi up/downhauls etc. I already feel like I should have bought shares in Spinlock so I am resisting that route.

Just playing with different possibilities at the moment to see which I like best. Going forward to reef in the N. Sea when banging to windward in a good breeze isn't much fun - dropping the main and hooking the tack is OK but I find grinding in the clew with an underboom winch on a rotating boom challenging. And I know I could have made my life easier by heaving-to ... :o

We're heading down-Channel at the end of the month (Belgium->Cornwall is the plan) - based on the current weather patterns it looks like I'll get lots of practice at reefing to debug whatever I decide to try.
 
I dont know if it is any help but I have a boom with a half open end at the goose neck the reefing lines are attached at the outboard end of the boom to the underside which has a stainless eye fastened
http://www.reliancemarine.com/Product/2838/Slide-For-Boom-Groove-RWO-R4863/View.aspx
to the underside groovedirectly vertically below the appropriate reefing cringle.
The line is then taken up through the reefing cringle in the leech and back to the opposite top side of the boom through a metal plastic bullseye with a metal insert http://www.reliancemarine.com/Product/2548/Bush-8mm-Ferruled-Black-Push-Fit-RWO-R3044/View.aspx
this allows the reefing line to turn through 90' and forward to a double swivel ball bearing pulley attached directly under the goosneck swivel.

It would be preferable for them to go around an inset ball bearing pulley but I have not had problems with friction or wear.
In my case the goosneck has a convenient cast eye which the stainless captive shackle supplied with the swivel double block fits.As an alternative If you have a mast slot available you could fit a captive slide as on boom . This works for me as the lower front half of the boom is cut away at an angle allowing the lines to exit cleanly and the swivel point of the goosneck is within mm of the turning point of the pulleys.

Personally I would also rig single lines for the luff cringles on reef 2 and 3. I am prepared to leave the cockpit for no 1 reef. I am not when conditions for 2 and 3 prevail.

Swmbo can easily hand pull the lines with final tension put on with the cabin top winches..
 
reefing line turning block at the goseneck

On my old boom I had the reefing lines on the outside (underneath) and simply shackled with a saddle rivetted on a 3 sheave block under the boom and as close to the mast as possible. The lines turned to g straight down to turning block on the deck then aft to the cockpit. There seem to be no problem with the boom swinging out even though it would tend to tighten the reefing line a bit.
On my new boom I have the reefing line and outhaul internally and I made a double sheave block that fits inside the boom near the gooseneck and takes lines again straight down.
i agree as others have said use a tack pennant rather than hook. If you sue a hook use a shackled welded in so you can fit a pin and lock the sail eyelet in. it will tend to want to escape otherwise. good luck olewill
 
TSB240 said:
Personally I would also rig single lines for the luff cringles on reef 2 and 3. I am prepared to leave the cockpit for no 1 reef. I am not when conditions for 2 and 3 prevail.

..
Click to expand...

Hmm - I hadn't thought of doing that. I think I was fixated on having adjustable (from the cockpit) clews for all reefs. But thinking about it, it's not very often (ever?) I have adjusted the outhaul on a reefed sail - it is pulled down to the boom and that's it. Not even sure if it is possible to adjust the sail in this way as the line pulls the clew both down and outward.

It's true when I am putting in the first reef conditions are usually fairly easy - it's reefs 2 and 3 that are challenging.

Or alternatively I could say that I am forever taking in and letting out reef #1, reef #2 gets used less frequently and reef #3 gets used about once per season. So I could route reefs 1 and 2 for convenience and leave #3 at the mast. Would avoid all the string of reef #3 in the cockpit too.

The first two reefs with separate tack and clew would use four jammers and and the tack pendants would pull straight down to the mastfoot perhaps via a couple of bullseyes to give a slight bend if required.

I think I'll fit the first two two reefs to be handled entirely from the cockpit and leave #3 at the mast - that way I won't have to call the offduty watch for a reef in/out either (except in reef #3 conditions - when I hope I would not be needing to wake them up) :)

Just need to figure out where to route the spi uphaul now ...:(
 
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