[Ian McColgin]

Ahoy Bill,

I'm thinking that what you've called the boom crutch is what I know as a boom gallows - a permanent installation with two legs some distance apart with a notched plank to recieve the boom. In our usage over here, a boom crutch is usually a one legged critter that's removed for sailing and really looks like a crutch. Sometimes the removable sissors type of bi-ped is also calles a crutch.

Anyway, sheeting to the gallows is not generally good, even if it's strong enough, as the sheeting angle is too high to give you any flattening power when on the wind. A vang works off the wind but on the wind depending on the vang to fully flatten the sail imposes qu ite a strain on the boom.

Getting the sheet to the deck can be a challenge with a gallows in the way. Usually bringing the sheet down aft of the gallows invites tangles. I'd incline to putting the blocks on deck a foot or so ahead of the gallows' base and of course having the blocks on the boom ahead of the gallows.

I'd personally tend towards a simpler rig of less mechanical advantage - one block each side of the deck and one in the middle, a double hanging on the boom with shivs normal to the boom. Run through one side block to boom, back to mid block, boom, and out other side block. I rigged a Rhodes sloop this way, 500 or so foot main, to the owner's complete satisfaction. Plenty of power. Even though the loads equalize, tweeking on the leeward end does bring the boom down more than in because of the block angles when close hauled.

On that Rhodes, there was a nice post at each aft corner of the cockpit so we did not bother with cam cleats.

If you are well crewed, you can speed trimming or easing, especially when gybing by having a person hauling each end.

I personally love double-ended sheeting but there is a bit of random walk in the sheet. Make two siezing from some thread of contrasting color at the mid point where you'll see it when the sheet is centered on either side of and above that mid-ships block. That helps you remember which side to trim first.

I am changing my catboat's sheet from single ended at 5:1 to double at 6:1. I don't really need the extra leverage but catboat sheets are long. When the boom is out on a run, the blocks are 35 feet from the deck blocks and traveler. When I go double-ended I'll trade one nearly 185 foot coil for two seperated 105 coils.

Oh, last point, all four of these blocks should be on swivels. The exact fairest lead changes as the boom goes in and out. Even if you put a spring or short bit of clear plastic hose or something between the block and base for the deck mounted blocks, it's also well to make a nice mat to protect your deck.

G'luck

Ian