Rerigging the Boom

Adjustments made to a Saber 30's block and tackle and outhaul make all of the difference in sailing performance.
Rerigging a sailboat boom
The reef hook/tack assembly (left) at Ora Kali’s gooseneck required some adjustment. To pull the block-and-tackle into approximate ­position inside the boom, I used a messenger line, then ran a screwdriver through holes in the boom and the shackle (right). Ann Hoffner

The mainsheet on our new Sabre 30 didn’t look right. It was the middle of a hot, airless July week. We’d bought the boat barely a month earlier, and now we were attempting to get it from New Jersey to Maine. Because of the lack of wind, the mainsail sagged as we motored up Long Island Sound. I had plenty of time to look at Ora Kali’s boom but not a lot of incentive to solve any problems. 

Then one day, we were tied to a mooring in the harbor at Scituate, Massachusetts, cheek by jowl with another Sabre 30. Wow, I realized: Our ­block-and-tackle arrangement is just wrong. 

The weight of the boom and pressure on the mainsail on a small boat are light enough that the connection between boom and hand can be direct, but a boat of any size requires an arrangement of block-and-tackle to make it manageable.

Block-and-tackle reduces the forces necessary both to hold something in place and to lift it. In terms of mainsheet tackle, a block-and-tackle system makes it easier for the person in the cockpit to steady or control the boom and to sheet in the sail when there’s wind.

Ora Kali has three blocks in her mainsheet tackle. While the arrangement on the port side was fine for holding the boom in place, it did not take full advantage of the power for sheeting in. I took down the blocks and rearranged them. The correct arrangement gives a 3-to-1 advantage on the aft block-and-tackle, and employs the forward block mostly for turning.

The sloppy mainsheet tackle setup shouldn’t have been a surprise. This was not the first instance of the boom being rigged wrong. But Ora Kali was in such good shape for a 38-year-old boat when we bought it that I assumed something this basic would be correctly run. 

When the seller bent on the sails the day before the sale, I was still dazzled by our good fortune in securing the boat and didn’t take careful notice of what he was doing. A week later, we took down the mainsail before we sailed off to inspect it for wear that might need repair and noticed that the tack cringle was hooked onto one of a pair of hooks normally used when reefing the sail. It became obvious why this was done: The gooseneck fitting was set up backward, putting the attachment point for a tack shackle behind the hooks. Useless. In fact, it turned out there was no tack shackle. It was a simple matter to reposition the reef hook/tack assembly, and I eventually found a tack shackle that fit. 

Another puzzle we chose to work around in the interest of setting off for Maine was a barely functioning outhaul. An outhaul is used to tension the foot of the mainsail and attaches to the clew or clew car, then runs to the after end of the boom and around either an internal or external sheave and forward, where it can be adjusted. If the sail is fixed to the boom with slides or bolt rope, as it was on Oddly Enough, our Peterson 44, then an outhaul isn’t crucial for setting the general sail shape. In fact, we rarely touched ours. 

With a loose-footed main, the outhaul has more work to do. The Sabre 30 is the first boat I’ve owned with a loose-footed main, and I didn’t understand what the rig was. The rope that attached to the clew car was not the same rope as emerged from an exit plate forward on the boom. When we tried pulling on either end, the car would budge only so far, and we never were able to fully stretch out the loose foot. I assumed that the outhaul had broken and a knot someone had made to add new rope to the original was jamming inside. 

Correcting the rigging
The original rigging (left) was fine for holding the boom in place, but it did not take advantage of the power for sheeting in. Rearranged correctly (right), it gives a 3-to-1 advantage on the aft block-and-tackle. Ann Hoffner

During the spring refit, I looked up in-boom outhaul rigs and saw that they usually include a block-and-tackle to add purchase for adjusting the mainsail foot. This is fixed midway by a bolt through the boom. I took Ora Kali’s boom end off and discovered that the bolt holding the block had been run right through it rather than through a shackle, keeping it from swiveling. The two pieces of line were too big to run alongside each other freely. Between a seized block and the friction built up in the lines, the outhaul was useless.

The tricky part of this rerigging was snagging the shackle. I used a messenger line to pull the block-and-­tackle into ­approximate position inside the boom, then ran a ­screwdriver through holes in the boom and the shackle.

The last piece of boom ­rigging that bothered me was the topping lift. On Ora Kali, this was a fixed length of ­7-by-19 wire rope attached at the masthead with a small block at the other end. A Dacron rope ran from a shackle on the end of the boom, up over this block, down to the boom end sheaves, then inside to an exit sheave.

This is a fairly common way of rigging a topping lift, but I’m not a big fan of using wire in running rigging. 

The primary purpose of the topping lift is to take the weight off the boom when the sails are furled and for reefing. On my previous cruising boats, I had topping lifts that doubled as a spare main halyard. 

To fulfill both of these needs, I replaced the system with a single rope outhaul, shackling one end of the new topping lift to the after end of the boom, leading the other end over an unused masthead sheave, and installing a halyard exit plate at the bottom of the mast for the topping lift to run out and be adjusted. The lift is simpler, which I like, but running it over a masthead sheave puts it more in the way of the mainsail leach. To make sure we ease it when the sail is raised, I plan to bring the bitter end of the topping lift back to the cockpit to an existing set of sheet stoppers and a winch on the coachroof beside the main halyard and the mainsheet.

All in all, I now have a cleaner, more rationally rigged boom. 

Ann Hoffner started sailing when she was 9 years old. Along with her husband, Tom Bailey, she spent 10 years cruising on their P-44, Oddly Enough, in the South Pacific, Australia and Borneo. Ora Kali, a nimble, shoal-draft Sabre 30, is now teaching them the joys of Maine coastal cruising.