Retrofitting a furling mainsail?

dinwood

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We're about to buy a 40 footer to go long term cruising (mostly Med), and having lived successfully with in-mast furling on our 33' Najad, were hoping to find a boat with something sumilar, safely handlable from the cockpit by the 2 of us. We've found a great boat, but it is conventional slab reefing, all lines at the mast. What are our options? Can we retrofit in-boom reefing (at any sensible cost), or is single-line reefing the only real option? Can anyone advise?
 
Depends what your definition of reasonable cost is! We fitted a second-hand Furlex-Main behind-the-mast furling system on our last boat. Last time I looked the in-boom systems were more expensive than the in-mast (behind-the-mast) systems. Either way you'll need a new main sail to go with it, so you're looking at several thousand pounds for the system, fitting and a new sail. You've also got the cost and hassle of leading the lines aft requiring new deck hardware and lots of hole drilling on coach roof etc. Perhaps you should keep looking in case you find another suitable boat with the the sail handling arrangements you want?

Jerry
 
It's uncommon to find a boat with behind mast, retrofitted furling, though the alternative of boom roller reefing appears more often. I suspect it is probably unsatisfactory.

The major advantage of in-mast furling is that you don't have to hoist that heavy main every time you set sail.
The disadvantages are that you have to have a hollow leech, because no battens, reduced drive and give up flattening the main by mast bend.

I was so fed up with the light winds in the Med that I had a 358 ft2 fully-battened main made to replace the 294 ft2 standard main. This overlapped the backstay by about 400mm and I had to put 4th reef in the main to bring the main down to working proportions.

This was an external line, bitter end at the boom end, to a block on the leech, then back to a cheek-block on the end of the boom and thence to a cheek-block on the boom close to the gooseneck, thence to a block on the mast and from there to the mast base and back to the clutches at the cockpit.
This has worked well for 4 years and I've just converted the 2nd reef to a single line.
I used Harken 46 airblocks (direct from the States), Kevlar 8mm line (since fatigued and replaced by Dyneema. Putting in the reef takes about 25-28 secs, and it can be done at any point of sailing.
Disadvantages - length of line, the 2nd reef is 22m long - and having to haul the main up in the 1st place.
Cost 22m line, 3 cheek and 2 pendant blocks, about 2% of any roller reefing system.

I have had heated discussions with Jim Baersalman over the desirability of a roller reefing main - OK for masthead rig boats, but not a good idea if you've a performance 3/4 rig lightweight.

I'd certainly recommend the single-line reefing, bearing in mind the necessity of avoiding frictional losses, the usual killer for attempts at a single line reef.

PS Had to go and cook lunch so this was delayed by 2:30hrs.
 
One disadvantage of retrofitting in-mast reefing is that it adds considerable weight aloft. I would suggest you look at getting a quote from someone like z-spars for a new mast. If you see the boat you want and this is the only barrier to buying it, put a new mast and standing rigging on the price and see what your budget looks like then. If it's OTT look again. The additional cost of a proper mast arranged for IMRR over a retrofit rivited on one should be considered rather than add lots more weight aloft IMHO.
 
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