| ||||||||||||||
|
Articles: It's the little things that count. Article by Geoff Moore
It appears without warning, the panic stricken face of a port tack skipper desperate to let loose the main. The tiller is pressed up hard under his chin, the left hand franticly banging the mainsheet, wild eyes, pale cheeks; it is just a flash of an image. Something you dont realize youve witnessed until much later. It is the face of impending doom.
When the boats are eventually detangled, and both teams realize that the race is over there is time to assess the damage. The victims are angry. They wonder why? Why didnt they just uncleat the main? It was obvious wasnt it? You cant duck a boat without dumping the main!
The criminal skipper has little to say. Guilt consumes his capacity for speech. He droops his head and repeatedly cleats and uncleats the unloaded mainsheet, babbling something about the high cost of insurance premiums. Over and over again the cleat functions perfectly. The guilty skipper is left alone without a shred of an excuse.
One of the more sadistic facts aboard a racing sailboat is that the load on the mainsheet increases proportionally with the proximity to right of way boats. That means cam cleats can become harder to uncleat just when you really need to. Uncleating cam-cleats is all about overcoming the load on the loaded side of the cleat. What most people dont realize is that a standard swivel cam cleat can be made to uncleat easier or harder.
The height of the ratchet block relative to the cleat is the critical adjustment. If your ratchet block is too low then you will have to pull the unloaded bight of the line at a very high angle in order to release it. That might be OK if the cleat is on the floor of the cockpit and you are seated directly above it, but it wont work very well if the cheat is up on a traveler bar and four feet to leeward. If the ratchet is too high relative to the cleat then the cleat wont hold, or it will constantly pop out when you dont want it to. In other words it will uncleat too easily.
The difficulty is that the ratchet and the cleat are usually very close together. That makes the relative angle between the two extremely critical. Unfortunately, it is not an easy thing to adjust. All the swivel bases I have seen dont seem to have any adjustment to the height of the ratchet block. So we are left trying to find the one mystical shackle with exactly the correct length, or we try bending the swivel arm. Swivel arms are specifically designed to do two things. They swivel and they dont bend. So why dont they make these things with an adjustable threaded stud under the ratchet so that we could adjust the angle to the correct sailing position? Well if they did that then everyone could uncleat their mainsheet at will and the world would loose the spectacular drama of high-speed sailing crashes.
The Spinnlock works on a different principle. It uses a cam to help lever the cleat open. That makes it less sensitive to the ratchet height. I have used both versions of Spinnlocks on a Harken swivel arm. The first version was a disaster. It just didnt work. It constantly uncleated itself and then it broke. It took a lot of convincing to try it again with the newer aluminum cam, but we did and it didnt break. However, we found it to be on the too easy to uncleat side of the spectrum. It popped out of the cleat at least once a windward leg. Usually that was because the skipper didnt have it fully cleated or he accidentally kicked or bumped it. It is an interesting idea though and it could probably work well if you became accustom to its idiosyncrasies. It would be even more interesting if you could adjust the pressure required to open the cam. In the final analysis it is hard to beat the simplicity of a well-tuned ratchet and cam-cleat assembly.
Whatever you use it probably wont win you the race, but do us all a favor and make sure you can uncleat it under load.
|
One
Design Classes | Tuning Guides
| One Design News |
Order | Contact Us | Home
|
© 1995-2005 North Sails One
Design. All Rights Reserved.
|