Movable Ballast

Hidden deep in the discussion on Heavy Weather Sailing are couple of comments on the moveable lead ballast in the GRP Romilly and there have been other comments about moving this ballast to reduce weather helm.

I suspect that some owners have experimented with this ballast over the years and would very much appreciate a sharing of ideas and discussion of the pros and cons of moving the ballast.

Nigel Irens said “Finding the right fore-and-aft trim is important to find the right balance between the dryness of the ride and sailing efficiency upwind. Moving crew-weight aft is the instinctive reaction as the bow rides higher and lifts more easily to a sea, keeping the crew dryer. The downside is that the fore-body can start to slam in certain sea conditions, and I suspect the boat is a little slower (any observations on that?). We ended up (by trial and error) with about 80 kgs of lead ballast, secured under the bunk forward.”

David Collin said “Nigel’s point about moveable ballast interests me greatly. I have always sailed with all three lead blocks of ballast under the forepeak berth, but I have sometimes wondered if they are there to counter the weight of a full crew in the cockpit. I have sometimes been tempted to take them out, on the theory that as I am always single handed, I may be carrying needless weight, and affecting the fore and aft trim adversely. Would removing them or reducing them be sensible, and could that reduce weather helm?”

    1. doryman says:

      Weight forward is the counter measure to sail area aft. Too much weight forward would result in an premature reef in the main – but possibly with no loss in speed.

    1. Nigel Irens says:

      The original idea with the internal ballast under the forward bunk was, quite simply, to have a way of lightening the boat for towing. Obviously this has a double effect in improving the towing equation because the same ballast adds to the mass of the towing vehicle.

      It is also true that carrying some trimming ballast also allows some ‘fine-tune’ in the trim of the boat. Bill Stanton (the first owner of the class-name boat) and I put to sea several times in one quite breezy day off Salcombe Estuary, carrying variable amounts of ballast forward, and testing different crew positioning at the same time.

      The bottom line was that with crew (two people) against the house at the forward end of the cockpit, we were correctly trimmed with little or no ballast forward. The only problem was that it was quite a wet place to sit. For that reason (and also to allow correct trim when sailing alone) we found it best to put about 80 kilos forward (under the bunk) this did do the trick in allowing the crew to sit further ft and stay a bit drier.

      I don’t remember helm ballast being the main issue here, it was just that if we sailed with crew weight too far aft, and no forward ballast, the bow felt light and tended to slam a bit as she fell off the crest – which is not what we wanted.

      My feeling is that you are more likely to need the full 80 kilos forward if you re sailing alone, but as it is easy to add/subtract ballast (ours was loose, held down by webbing belts), then why not conduct a bit of ‘trial-and-error’ yourself ? I would be particularly interested to know if you find the helm balance can be improved with less ballast. I’m sure you would then be able to throw new light on this matter, which I’m sure would be appreciated by other owners!

      Best wishes