BOAT -
I have not seen any boom mod on the market that converts the existing boom to a rotating one - maybe I missed one- can you point me to it? Most on the market are for larger boats that are able to tolerate more weight aloft. Or they have great efficiency losses by introducing way more than the 1/2" gap or so that sail slugs do. Or they have a separate roller that runs parallel to, and above the boom. Yoosh - but I guess it works.
I found a rotating boom works fine with slugs (I used it for most of last season) - but of course you need to provide an exit point (if you've closed it with a gate) from the mast slot, the same way you would with a bolt rope. The luff control issue I spoke of comes into play when you want to raise the main and guide the slugs into the slot. Without having to be present at the mast. That's the issue needing to be solved, and that's the issue that seems to be the monkey wrench in the gears of most commercially available systems too, according to reviews I've seen. None are perfect, and there have been some smart people, skilled in the art, working on it.
Having said that, I've been regularly sailing on 2 larger boats (Beneteaus) with in-mast furling (not appropriate for boats the size of our Macs) for at least the last 6 seasons, and they have performed essentially flawlessly. (Loose-footed main, of course).
I've come across a simple rotating boom mechanism on the market (CL boats) that fits into a square drive and square socket at the mast (sprung together) - you can just pull straight back on the boom to disengage the square directly from the cockpit and it then turns freely. No need to approach the mast. It's for small dinghies with small booms, though. But I have found that not to be needed on the Mac because the vang, which rotates with the mast, and traveller both pull downward on their bales to prevent the boom from rotating in the first place.
I have considered routing the main halyard up through the slot in the mast to eliminate the rotational tendencies that increase friction. But I won't be taking that route for sometime yet (out of keeping with the KISS principle), and hope I might see it in some other boats in the meantime. Anybody out there seen this? It seem logical that someone has done it.
The presence of the topping lift might seem to complicate things, but the way I've done it (proof of concept) is very simple, friction-free, and the crank attaches and detaches easily to the end of the boom (padeye) without any mods to it. That was the easy part.
The main reason you don't see rotating booms on (larger) sailboats much any more is because they didn't work as well as other systems that came to the market, and they were problem-prone, so, they ultimately complicated an issue they were meant to simplify.
- B.
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