Sail Halyard Mod (Convert from twin halyard to single halyard) Most owners have little or no problem with hoisting and locking their sails up using the standard twin halyard system. But no amount of tweaking to my own halyard could make it reliable. The halyard ring rarely locked onto the masthead hook, even with the sail dead in line with the wind. Several members offered advise, but nothing worked. Maybe it needs a technique that I can't master, but I usually had to capsize the boat on shore to lock the sail at the masthead. In desperation I turned my attention to the head of the sail and noticed that the top edge and adjacent luff around the head cringle was frayed and “floppy”. Was this allowing the sail to lean to one side when the halyard ring rode up onto the underside of the mast hook? If so, would a new sail be needed? Repairing the head material of the sail was easy though. I soaked the individual layers of the sail material with super glue, wrapped a piece of polythene sheet over it, and left it nipped up in a portable vice overnight. The result in the morning was near miraculous. The head of the sail had set like a solid piece of plastic. This was excellent! – Problem solved?.. well actually... No! The theory was sound, the repair was good, the result looked great, but on hoisting the repaired sail, not one jot of difference! At this stage I decided the twin halyard system was to become redundant - “sorry guys!” (It's probably just me.) If the actual problem had been discovered, I might have found an answer, but it wasn't - so I couldn't. Instead I converted my mast and halyard to a more conventional system. -----------------------------------------------------------------------------------------------METHOD ONE This is the single halyard system as used on Dart 18s and Dart 15s which works very reliably. In my garage, hung under the rafters, was an old, self made, two piece Dart 18 mast, complete with a hook and halyard ring. The temptation was too great, the fittings would be re-cycled! I don't roof top the Dart 18 since getting the Catapult. This alternative Dart 18 method, applied to the Catapult, works great! However, it is a little expensive unless you can obtain the parts second hand, or possibly make them yourself.

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(Before starting any work, please read “Method Two” further down the article) At the time of writing the masthead hook for a Dart 15 or 18 retails at £18.35. But if you have one to copy this could be made from cheap stainless steel off-cuts (Try eBay! 2.00mm thick should be ideal). The halyard ring retails at £15.15. and is more difficult to make. A shackle welded to one end of a “quick links” chain repair link, and a cut down washer welded on the other end, would do the job. The hook part needs pop riveting to the mast head as shown (Fig 1). Try to locate the vee of the hook centrally over the mast groove. The old redundant top hook (sandwiched between the brass pulleys) can be left in situ. Unused.

Fig 2

Fig 1 The over long rivets I used were sawn off with a hacksaw blade and tapped flat against a metal rod slipped down into the luff space behind. To prevent halyard chafe. The flattened rivets can be seen in (fig 2).

The ring needs fixing to the halyard as shown in (Fig 3). The knot should face away from the mast in use. Helps with releasing the ring. A handle can be added to the mast, to aid rotation for initial sail release. Though it works well without. Hoisting the sail is now easy, as the ring just slips onto the hook. To lower, raise the sail, then rotate and hold the mast to port while pulling the sail down a few inches. Release the mast and fully lower the sail. Keep boat head to wind. (Return to Repairs and Mods page) (Return to Catapult Home page)

Fig 3

Mast rotation handle shown “parked.” (Fig 4) This is some 7mm stainless steel rod welded to the end of the down-haul connector pin at the foot of the mast. In practice you can get away with rotating the mast by just pulling it round using the down-haul line. Procedure for hoisting - Attach the halyard ring to the head of the sail with the knot facing away from the mast (important). Point the boat head to wind and raise the sail via the halyard until the ring clicks onto the hook at the masthead. Pull down on the sail to check it's on. To lower the sail, point the boat head to wind, then pull on the halyard to lift the ring up off the hook at the masthead. Whilst holding it up, rotate the mast to port, (clockwise as viewed from above) then pull down hard on the foot of the sail as you slowly release the mast back to straight. Once the sail has started to move down, fully release the mast. Fig 4

METHOD TWO (An easier way) It occurred to me while writing this article, that it's a rare occasion, if ever, that any serious weight is put on the Catapult down-haul. So you could simply remove the masthead hook altogether and fit a standard shackle, onto the end of a single halyard. An open hook could be used in place of the shackle.

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After hoisting the sail, tension and secure the halyard at the mast foot area. (Tie it temporary initially) You can later fit a small clam or horn cleat to the mast foot if required. To hoist the sail- Attach the halyard to the head of your sail via the shackle and hoist the sail up the mast to its full extent. Tension and secure the fall of the halyard at the mast foot area. Fit and tension the down-haul as normal. Modify to Method 1 later, if not happy with the result. Note- Using a Dyneema® halyard will virtually eliminate any stretch.

Mast head and foot shown here may help.

Any comments or corrections are appreciated - [email protected] Feedback received 08/06/14 – Method two has been tried and ©reported as being successful. Dyneema halyard was used. No apparent stretch problems. Input courtesy of Malcolm Droy (Catapult owner)

Syd Gage, Catapult 506

First published June 2014 Updated Nov 2016

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