Option
Hi again,
Sorry to have been so long in getting back to this; we have had a lot of fascinating work going on here.
First, I can see why your version of 3:1/6:1 would produce a tangle. I'd be amazed if it didn't. But let's not condemn the idea because of, um, alternate takes. Stacking a Harken 2138 on top of a 2139, and anchoring the latter to your cockpit sole fitting, would give you leads coming out one above the other, with both or either available for hauling or slacking, tangle-free. You might experiment with cam angle, and orientation, for best ergonomics for your situation.
The boom block for this setup would be a double with a crossblock on it (the upper part of Harken 400), and the lower block would be a double.
Alternatively you could have a double block on the sole, with side-by-side cams on a swivel arm (Harken 402). In your case, I think this would only work if the arm could be bent wa-a-y up, to get a usable angle on the cams; check with Harken on the feasibility of this.
Two-speed purchases only work if it is easy to handle either or both lines. That precludes having them exit anywhere but right next to each other.
There are other ways to do this, of course. On a fairly large cutter we are working on now, for instance, we have one lead going to a self-tailing winch, and another going to a rope clutch. The clutch is positioned just outboard of the (port-mounted) winch, so it is easy to grab both it and the line coming off the winch. Most often in a boat this size, though, the crew will take up on the clutch line for low loads, and use the winch for taking up high loads as well as for slacking for either low or high loads. And so on.
Fair leads,
Brion Toss
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