Rocking and Rolling

[Voltair]

Well, I don’t know about your Nic, but Voltair tries to tip me out of the bunk when at anchor in anything more than a heavy dew.

We have been mainly anchoring all around Ibiza for a week or more, since the marina fees are outrageous. Waves on the bow or stern, no problem, but a mere 3″ high swell from abeam, and the glasses are on the floor, the jars in the cupboards are jangling, horrible!

So we have been building on previous experiments and think we now have it cracked!

Reqd: 1 large bucket, 1 set diving weights 15kg approx, Spinnaker pole, rope + one random but quite large piece of driftwood such as a dinghy thwart.

Tie weights to wood, and tie wood to bucket between handle and rim. Tie bucket to rope and suspend 3ft underwater at end of spinnaker boom, set abeam and held up by spin halyard, since uphaul is holding up our black ball.

Result, we are rolling less than any other yacht in the anchorage! My GnT is staying where I put it even though there is quite a lot of activity in the bay.

[Van]

Yes, we roll too – especially when the frequency of the wavelets seems to be close to the resonant frequency of the boat.

We had similar luck reducing the rolling by taking a large plastic cutting board, about 20 x 30 inches, drilling holes in the 4 corners, and tying four lines through each hole so that the board could be supported horizontally from another line. Each of the four lines also went through the board down to a large lead weight (also about 15kg) about 2 or 3 feet below the board. Then this contraption was suspended from the end of the boom with the boom held as far out as possible using a preventer, and dangled into the water about 3 feet deep. Worked like a charm! But I do find the 15kg of lead a bit unwieldy – potential toe/finger smasher.

[Ronar M]

I have heard of a variation – a flopper stopper that avoids the 15kg. I have always intended to make one but have never got round to it so don’t know how well it works. It’s a equilateral triangle of plywood or plastic of side about 18 inches. There are 3 holes, one at each corner to take ropes which join a couple of feet above it into a single rope which is suspended from the boom. One corner of the triangle is weighted with a lead disc so that corner dives as the boat rolls down. As the boat rolls back the triangle becomes horizontal again and resists the roll. I am told it works well.
One reason I haven’t made one yet is that I usually find that rolling at anchor is due to the boat lying across the wind and swell. So I put the mizzen up and that turns the boat into the wind and prevents rolling. Good luck. Trevor

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