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Old 09-15-2002
Tom Wood Tom Wood is offline
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Stepping the Spar

How can I step the spar on a C&C 26? It appears to have a mast step that pivots the spar from the front of the boat, possibly using the boom as a lever.

Tom Wood responds:

While I am not familiar with the exact setup on your boat, deck-stepped masts on tabernacles for raising and lowering without outside assistance are not unusual. We have such a rig on our 40-foot Sojourner and I have seen European boats as large as 50 feet with lowering rigs like the one you describe.

On the average 20-foot boat with the mast pinned into a tabernacle, one person can grab the spar, pushing it up hand over hand, while a second person helps keep it under control with a halyard and then pins the standing rigging. On boats over 25 feet or so, however, the process becomes more complicated. The weight of the mast with attached running and standing rigging becomes unmanageable for one person and the lever becomes larger, making mechanical aids necessary. Also, in the event of a control failure, a big stick makes a much larger crash than a small one, with consequently greater bills for damage.

The first problem is to control the masthead, not allowing it to drift either port or starboard during the ascent or descent. As soon as the mast is lowered a foot or so, the headstay, forward lower shrouds, and uppers go slack, giving no support and most tabernacles are not strong enough to resist the force of the mast if it starts to lean to one side. On really big boats the way to solve this is by building the upper shroud chainplate pins on the same plane as the pin in the tabernacle. This allows the upper shrouds to remain taut, maintaining control over the mast from side to side. On a 26 footer, you could probably accomplish this same thing by posting two able-bodied crew port and starboard with two masthead halyards rove through strong cleats.

The second problem is that the angle of attack of the control lines aft becomes more and more acute as the spar approaches the horizontal, offering little or no leverage over the desire of the mast to fall forward faster and faster. In fact, with the stick all the way down, a line led from the masthead to the backstay chainplate will be parallel to the mast, giving no angle whatsoever. One or two crew can probably lift the mast into place, forcing it upward by walking aft and pushing the mast over their heads as they go. But there is this awkward spot where they have the mast at such an angle that its weight is becoming too much for them and yet the angle for the aft line is still too little to be effective. The answer to this problem is a giant spreader, called a gin pole, and the boom is usually just the right length.

So here’s what we need. With the mast pinned in the tabernacle and laying forward across the padded bow pulpit, we first pin the headstay (over the top of the pulpit). Then we pin the boom to the gooseneck and attach the (strong) topping lift to the outboard end of the boom. The handy, extra-long 4:1 mainsheet is attached to the bottom outboard end of the boom and led to a really strong point in the cockpit. Since the boom isn’t going to want to stand right straight up in the air without falling port or starboard, we attach two lines to the outboard end of the boom. We assemble our crew of eight like this: two on the masthead halyards placed slightly aft on port and starboard to control the masthead, two on the boom lines to keep the boom from swinging port or starboard, one in the cockpit to take in on the mainsheet, two on the bow to lift the mast and walk it up as much as possible, and one "floater" whose job is to straighten out tangled lines, unhitch stuck shrouds, and help where help is needed.

When the mast is up as far as the pushers can push, they can go aft and help pull up on the mainsheet until the forestay comes taut. When that happens, one of the (now three) cockpit crew pins the backstay, while the two boom controllers pin the upper shrouds. When this is accomplished and the turnbuckles tightened to keep the mast standing, the adrenalin-induced excess energy should be worked off with a round of cold beers—at the captain’s expense, of course.