Mainsail reefing

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wgarnier

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I have an Achilles 24 with a Proctor rolling boom. This is an awful arrangement and I need to install a single line reefing system which will allow me to put 2 slabs in from the cockpit? I have been quoted some large figures to replace the boom, so large in fact that it occurs to me that there must be a diy system that could be installed.

Are there any ideas that could be conveyed on this forum or directions to more information.

Much appreciated.

William
 
There is a system which relies on blocks fixed to the external side of the boom, but I cannot remember if it is single line or not. Arun sails (Ivan Bole) once provided me with drawings but I passed them on to the chap who bought my last boat. Have you considered using a two line to the cockpit system? You end up with a bit more string in the cockpit but less friction when you reef.
 
William,
putting in an existing boom two slabs of one line reefing requires to apply, trough drilling and riveting, one half ring (to tie the fixed end of the line), a pulley on the other side of the boom to pass the line as it comes down from the mainsail, another similar pulley on the same side of the boom at the foremost end and then, according to how your mast foot is organized, a cleat or another pulley to allow bringing aft the line; this You have to to for the 2 slabs, totalling at least some 6 holes per slab; can the boom carry that?
Also keep in mind that the simplest way is to fix the fittings on the outside of the boom, so You risk ending winth dangling lines.
Best would be to have the fittings on the inside of the boom, which implies removing the existing fitting at the ends and see if it is possible to drill the holes for the fittings AND 2 for the line, which in turn could require fixing some fairing.
Not difficult but ennoying and appropriate only if the boom is a bit "overengneered".
Best luck,
Gianenrico
 
We converted ours to a single line reef.
Starting at the aft end, the line attached to the boom, up through the leech reef cringle and direct back to the block in the back of the boom.
Through the boom and up at the gooseneck, through the luff reef cringle and down to the foot of the mast.
Through a block and led back to the cockpit ...

I did have to reduce the size of the lines (now 8mm) and may well change the second reef so it acts like a 2 line reef, but spliced into 1 line on the deck.

A search in this forum for around a year ago should give a result on other posts....

slrboom.gif
 
Hi Fireball,
My slab reefing "system" is a bit more primitive and I've wondered about changing it for a single line system, but looking at your diagram, I can't see how you get any tension along the foot of the sail when reefed? If I don't do this on my boat, the sail ends up horribly creased and baggy, nearly as bad as the old roller reefing around the boom.
Dave
 
This is yet another thing I've been looking into, since my boat has a roller boom converted to slab, using clew lines from the end of the boom and claws at the gooseneck. I'd like to use something a bit neater, but I've only seen the Barton system available through Plastimo/chandlers. I am debating that best compromise would be use a system like above illustrated, and once this is set in, quickly pop up and tie off the regular reefing lines. Not ideal, but quicker than using the claws. Only thing I need to adapt is the lines at the gooseneck and add the blocks on the sail and deck/mastfoot.
Jem.
 
Move the aft end tie off point further aft ....

I must just say that without blocks on the sail this system has "quite a bit" of friction. It does work, but is not a smooth reef. A 2 line system may be better if you reef and shake out often or don't have many active bodies on board!!
 
with lots of help from Harken

in the US, I fitted a most effective single-line system, coming back to the cockpit, on my boat with a far larger main then yours.

It's using the big Airlite blocks and a kevlar line - the dyneema one is sitting waiting for a failure.

The problem with most systems is the amount of frictional resistance you have to overcome, inherent in the Barton system.

If you like to send me a PM with your e-mail address I'll send you a diagrammatic representation.

I'm now seriously considering converting the other three reefs to a similar system - only trouble is the plain-bearing pulleys in the reef-pennant in-boom assembly.
 
I am in the process of converting my proctor boom to slab reefing, and to get round the problem of lots of holes in the boom I am fixing a long s/s plate to the side of the boom. This will carry the cheek blocks and line jammers.
BTW I won't be doing anything to the gooseneck fitting - just wrapping a strop round it with krabs to clip the rings to.

The cabin top would take too much reconstruction to lead lines back to cockpit so am not bothered about reefing from the mast.
 
System illustrated by Fireball works ok, but there is quite a lot of friction and you end up with miles of line in the cockpit.

Instead try this:

1) usual line from boom, through leach reefing point, back to cockpit via boom and foot of mast.

2) another line fixed to the mast end of the boom, up through luff reefing point, back to cockpit via a block at foot of mast.

OK so you need one extra block, a bigger deck organiser and an extra jammer or cleat.

But it works great - Let down sail to a point marked on the main halliard, pull in leff line tight, pull in leach line tight - bobs your uncle.

We only have this on 2nd and 3rd reef as 1st reef isnt a hassle
 
Re: Mainsail reefing and Fireball\'s post

How big is your main - mine's just over 350ft2 and without the exceptionally free-running Airlite blocks it was almost impossible to pull in when under way with conventional blocks.

There is also a cheek block on the mast just below the boom, allowing the last few mm of reef-luff to be pulled down.

You can get small inserts from Rutgerson, which replace the normal reef cringles, with a small roller inside them.

I haven't tried them, rather concerned about the load-concentration on the axes and their very small size.
 
If you use 2 lighter lines on the sail you can splice these into a larger sleeve to go through 1 jammer ... you need to do it so the 2 lines just come through the jammer when reefed so you can tension them up indepedantly...

the "miles of line" in the cockpit is ok if you've got a deep sprayhood that you can put it under ....

Friction isn't too bad, but you do need easy access to the topping lift ....
 
I've basically got the same system as Fireball, axcept that the reefs are on opposite sides of the sail. By having blocks on the sail, friction is kept to a minimum. Also there appears to be no problem in getting the tension on the foot of the sail right.
The biggest advantage is that I can put a reef in in about a minute, and take it out just as quickly.
 
Re: Mainsail reefing and Fireball\'s post

Erm ... dunno how big the main is - it is just over 30' mast, but the gooseneck is a couple of foot up and the boom is just over 3.5m ... (Jenneau SO 30) ...

I drop off the power in the main whilst reefing and the sail drops reasonably freely so friction isn't too bad, the lines do run straight through the cringles with no blocks in the main (at the moment).
Interested in the blocks you mention - any links to suppliers? I asked the chandlery and they hadn't got a clue what I was talking about!! I think these might just sort out our reefing system completely ....

As I've spent a grand total of about £20 on the reefing system - ie 2 ropes ... I think we could splash out a little extra on some good sail blocks ...! /forums/images/graemlins/smile.gif
 
Re: Mainsail reefing and Fireball\'s post

I've got Proctor roller reefing, but I'd have trouble finding the crank handle. I just go home if it gets too much. If I can't stay on the cockpit seat it's getting a bit breezy.

(Yeah I know you've got more serious considerations at sea.)
 
Re: Mainsail reefing and Fireball\'s post

We had that on the last boat ... couldn't be a*sed to reef the main ... so either had it all up or none up ... boy we had some good runs! Had to take fairly often otherwise you get all stiff bracing yourself in one position!

The solent isn't much different to a lake - except for the waves ...
 
Re: Mainsail reefing and Fireball\'s post

When I had to ask father-in-law not to turn round as we were running dead-down wind (just jib!) and the waves were breaking above him .... we were fine ... didn't drop below 7knots in the little 22'er ! /forums/images/graemlins/laugh.gif

No reef either! ... no sail !! it was F7-8ish ... and we only had to run downwind .. /forums/images/graemlins/laugh.gif
 
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