A question of balance

Gwylan

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There has always been a small puddle of water that collects in the starboard corner of the cockpit on our Westerly Seahawk.

This last week I got a chum to come and help me set up the mast and rigging for the anticipated season of sunshine and sailing.

Well, as we started, waiting for the boat to float off the mud berth I put the spirit level across the cockpit. As the boat rose the un-evenness in the level did not go away. Even when fully afloat the boat remained lop-sided.

This was a bit of a surprise for me.

So now fully afloat I put the level across the cabin floor and got a similar result.

The engine, diesel and water are all along the centre lines of the boat. There are no other major weighty items on one side or the other. With 3 adults [230 kg] all stood on one side of the boat we were eventually able to restore some of the in-balance.

Based on the present sailing performance the mast is probably not vertical. Could it be that bad that it causes the whole boat to have a distinct lean to starboard?

Should I worry, do anything or just set the mast vertical and continue from there?
 
You could check your theory that the mast isn't perpendicular to the beam of the boat by taking a photo from exactly bows-on and printing it out. Then check that the stem and mast are in the same line. Sounds rather roundabout but I have a pic. that someone took of our dayboat when she was heeled at 30 degr. and it's very revealing - the mast as a whole is tilted a few degrees wrt. the stem and is deformed into a slight S-shape by the compression applied by the windward spreader. A camera plus ruler and setsquare make a powerful combination. Once you have corrected any such rigging errors then check behaviour of the cockpit puddle again. If still lopsided then you'll have to think about storage within the boat and get the heavy stuff segregated from the light, bulky stuff and store appropriately.
 
I don't think it's unusual for a boat to be slightly unbalanced. Although efforts have been made to place tankage, etc along the centreline there are still others, like the stove and batteries which are often to be found along one side. I found that my boat lists to starboard at her mooring unless I remember to move the liferaft into the port quarter berth. You'll just have to go through the lockers and see how much weight you can relocate. My mast is vertical to the hull lines (I hope) on the assumption that the hydrodynamic forces take over once sailing. Apart from allowing all rainwater to drain, getting her level gets an even brown stain all round.

Rob.
 
If the mast is off plumb, the leverage effect (weight x height x degrees out) could be enough to cause an imbalance of 230kg at deck level, I guess, especially if there's lots of gubbins at the masthead, and/or a radar scanner part way up.

Run a steel tape to the masthead on a halyard. Then measure the distance to the deck edge P&S. Best way to tell.
 
I agree with Ken, use a tape measure, the yard hardly ever put the mast up straight, I always check. However this year to my surprise it was spot on.

Obviously the taller and heavier the mast the greater will be the lateral imbalance per degree out of true.

There is however another possibility, perhaps more likely on an old wooden boat. The keel may be not on the vertical. This was certainly the case on a couple of the local One Designs that I used to race. Quite obvious when they were laid up.
 
As ever sincere thanks for the insights. Still a bit of a mystery.

Never thought about the liferaft, but that could contribute.

It was measuring from the masthead to a fixed point port & starboard that alerted me to the idea that I might have a problem and hence an explanation for the tack dependent performance.

Heh ho,
 
It's not unusual for boats to have a list with standard trim. Both Moody and Westerly brands suffer this way.

I had a Westerly Berwick with a list to port (well known design fault)
I now have a Moody 346 with a list to port (well known design fault)

I corrected this on each boat by adding a little ballast
 
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