USING LAZY JACKS
The most common problem encountered when using lazy jacks on a mainsail is fouling the headboard and battens while hoisting the main.
One cure for this problem is to slack off the lee side lazy jacks, or both lazy jacks, and carry them forward to the shrouds or the mast while hoisting. For example: If the main halyard leads down the starboard side as it does on most boats, slack the port lazy jack and hook it on a cleat on the port side of the mast. Then head the boat so that the wind is from about 10 to 20 degrees, an the starboard bow and start hoisting the mainsail. By keeping the wind on the starboard bow as the main goes up you will also keep the sail off of the person pulling on the halyard and keep the boom away from the crew in the middle of the, cockpit..
Once the main is set, the lazy jacks may.be left forward out of the way so they cannot chafe the main or simply left set up at the predetermined correct tension. The correct tension is: when the lazy jacks become taut when the main sail is lowered and the weight of the boom is taken by the topping lift and slack enough not to cut into the sail when the mainsail is hoisted all the way.,
When lowering the mainsail, the lazy jacks should present no problems. The leech of the sail will not fall all the way down by itself To help it down, once the luff is pulled all the way down, pull on the leech and the sail will lay neatly between the lazy jacks.
THREE PART LAZY JACK SYSTEM
Numbers below refer to numbers on drawing.
1. Lazy Jack lines of low stretch dacron. Use 1/4 on a thirty foot sloop and 3/8" on a fifty foot sloop.
The Lazy Jack lines should be arranged approximately as shown.
2. Seize on or splice in tightly; bulls eyes or round (sail) thimbles of brass or stainless steel. These should have an inside diameter about twice the diameter of the lazy jack lines
3. Strap eyes on boom beginning 15% forward of the clew and then evenly spaced. The lazy jacks may be secured with snap hooks if you plan to tie your lazy jacks forward, out of the way, for bending on your sailcover or hoisting sail etc...
4. hang a small block from your mast, 50% to 70% up.
5. Cleat to secure the fall of your lazy hacks. The lazy jacks may also be adjusted on the boom, but this is not as convenient when the sail is lowered.