Adding a weight to mainsail head to aid dropping.

WindyWindyWindy said:
Does it?

15m mast 1Kg moment of 150Nm, if instead stood 1.5m abeam of the mast on deck would be like having a 10L fuel tank strapped to the guardrail.
I know many who wouldn't bat an eyelid at that, but maybe I've got something horribly wrong there.

I wouldn't say that clambering around the deck is a problem, just that it'd be nice not to need to. I was also considering reducing the halyard diameter to 8mm, but not sure what load one should expect a halyard to take.
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As with most things in life, it's not that simple. The main thing that simply considering the moments ignores is the angular momentum. Your 1kg at 15m will have a lot more effect on the pitching/rolling motion than 10kg of fuel on the rail.

Second, consider the centre of gravity of the small weight, compared to the centre of gravity of the vessel. At equilibrium, the centre of gravity of the small weight will act vertically downwards, through the centre of gravity of the ship, and will not induce listing moment.

However, as the ship rolls, the transverse moment increases as the distance between the two centres increases. The theoretical biggest effect would be an angle of 90 degrees, since that's the largest transverse distance between the centres (ignoring the fact that then the weight would be in the water, and you'd have to consider the buoyancy of the weight, and ...


Anyway, none of this is really that relevant to the question at hand, which is how sensible it is to do this (IMHO, not very, but not really for these reasons). And now I've given myself flashbacks to ship stability at college. If I start mumbling about metacentres into my beer this evening, you know why.
 
As many have said, just a little excess friction. But any sail can get balky the last few meters in a strong wind. You can either add another string to fool with (a down haul), or you can go forward.

forums, IMO, are like a watercooler conversation among strangers. Both questions and responses are too brief to be complete, and you don't know the people. We can either waste a lot of time on polite niceties, just blurt out what we think, or give measured answers. We can either stay in the conversation or walk away, and either become offended or not. Best to pull up your big boy pants if your going to stay.

The day I can't and don't walk the length of the deck underway is probably the day I walk away from sailing. I enjoy it, even in moderately strong weather. I feel it is a skill that we need, and a skill that is only maintained by doing.

I'm all in favor of solving problems that require me to go on deck to sort them out. But you must also weigh if the solution adds more complication than the problem. In this case, the solution depends on the size of the boat (the OP does not have any information in his avatar--he will get better answers if he adds some), the track/sliders, the sail type etc. Best to give as much information in the first post as possible.

I've often had to pull the last bit down, on several boats. I have to be there to secure the halyard against slapping, secure the head of the sail, and probably something else. I never thought of it as a real problem.
 
Neeves said:
….You surely do not want me to agree that it is commendable to be scared witless about the idea of being unable to douse the last 2 metres of sail because you are unwilling to crawl to the mast, clipped on, well secured when you get there…
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What? I never mentioned being scared witless about going to the mast, nor I think did anyone else. It’s just convenient not to have to sometimes. Do you think I’m a big scaredy-cat because I have reefing lines led aft?

This is one of the most peculiar threads I’ve started on here. Whilst I was kind of expecting to be told it’s a foolish idea I hadn’t quite prepared myself for the fire and brimstone oratory!
 
fredrussell said:
What? I never mentioned being scared witless about going to the mast, nor I think did anyone else.
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I didn't mention it, but I do recall deciding that, even though getting the main down was the thing to do, I'd settle for furling the rest of the genoa, as I could do that from the cockpit. 30+ knots off St Albans head is a bit much for wandering around the foredeck on a Snapdragon 24. It a wasn't coincidence that I sorted out all lines to the cockpit shortly afterwards. When I found that gravity didn't bring the main all the way down, I added a light downhaul.

4mm line close to the mast won't add a measurable wind resistance, and it won't flap around if it goes through a couple of sliders on the way down. The cockpit end was permanently tied off to the small cleat near the clutches where I tied it off to hold the sail down , and was just long enough to allow the sail to go all the way up with little slack. It really didn't get in the way.

I won't say a weight is a bonkers idea, but I am convinced that a downhaul is a better way to do a better job - a bit of string, a couple of small blocks and a little cleat. Once I'd pulled the main down and made off the downhaul, the sail wasn't going anywhere and it could sit there until we were alongside or the anchor was down and the kettle on, no matter how bouncy things were at sea.
 
Something else that might be worth mentioning are internal halyards. Although clangy, I prefer the outside one's of old. You could at least know what's going on. With old boats it is difficult to know exactly know what has accumulated inside a mast . Mine could certainly run freer than they do. Perhaps I could hire one of those special cameras next time the mast comes down.
 
As one whose mainsail has in-mast furling, it's interesting to stand on the side lines here. Obviously with in-mast furling, there's none of this going forward to the mast to pull down the last wee bit of sail, and fiddle around with halyards etc. I'm not suggesting that it's a better system - that would open a whole new can of worms.
However, our boat is a ketch, and the mizzen is rigged "conventionally" dropping down into a stackpack, so I have current experience of both types. Of course the mizzen mast and gear is much more readily accessible - none of Neeves supposed heroics are needed. A while ago, we were finding that the mizzen was getting slightly reluctant to come down. All that was required was some silicone lubricant on the slides, and now the sail comes clattering down all the way. Before adding weights to the head of the sail ☹️ or adding more bits of string, I would strongly recommend that the OP spends a couple of minutes lubricating the track and slides with a dry lubricant.
 
DFL1010 said:
As with most things in life, it's not that simple. The main thing that simply considering the moments ignores is the angular momentum.
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Indeed, but few would worry about a VHF antenna, TV aerial, wind instrument and flags up there..

Also a kg sounds a lot, I doubt it'd be that much especially if it gets a bit of momentum in the drop...
 
WindyWindyWindy said:
Indeed, but few would worry about a VHF antenna, TV aerial, wind instrument and flags up there..

Also a kg sounds a lot, I doubt it'd be that much especially if it gets a bit of momentum in the drop...
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Many boats have a radar, say 7kg, halfway up the mast, but I believe that this is considered significant. 1kg at the top will have some effect, but I don’t suppose that it would be noticeable - not as much as a furling main anyway.
 
I don’t think it will have a significant effect on boat motions, though I would be mildly concerned about the effect it will have on the main itself. I think it would cause premature wear of the attachment points to the slides and in light winds the motion at the masthead may cause the main to bang to and fro.
 
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fredrussell said:
My main drops very nicely, apart from the last two metres or so. To avoid the faff of going up there to pull last bit of sail down I wondered about attaching a weight to head board. Wouldn’t take much I would have thought - perhaps a kilo or so - not a huge amount in the great scheme of things?

Bonkers idea?
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How do you either zip up the sail bag or attach sail ties?

At some point you need to go to the mast.
 
johnalison said:
Many boats have a radar, say 7kg, halfway up the mast, but I believe that this is considered significant. 1kg at the top will have some effect, but I don’t suppose that it would be noticeable - not as much as a furling main anyway.
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I don’t think this boat is big enough to consider radar.

johnalison said:
I put sail ties on when berthed. I believe that the risk of doing this is acceptably small.
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Ha ha, if you can’t walk around on your boat when moored, you either need to not moor in Studland bay in an Easterly, or else you really are too old!
 
Chiara’s slave said:
I don’t think this boat is big enough to consider radar.


Ha ha, if you can’t walk around on your boat when moored, you either need to not moor in Studland bay in an Easterly, or else you really are too old!
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I mentioned radar as an example of how weight can matter, depending on how much, and the boat of course, following the discussion about the effect of weight aloft. I have my radar on a pole at the stern partly for this reason but there are probably many small boats around with radar that will be suffering some adverse effects, if only in comparison to their un-radared sisters.

Yesterday I walked round the boat under way to position the fenders and felt a bit guilty about it, so maybe I am getting too old.
 
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