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Old 09-24-2007
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Quote:
Originally Posted by SEMIJim View Post
Somewhere between 15 and 20 kts, we'll be putting a reef in.

If we get 30 kt gusts w/o a reef in, we've done something very wrong, IMHO. I'm not saying it couldn't happen, but it shouldn't happen.
I don't know the waters that you are sailing in Jim; but some days out here in SF Bay we get light/moderate winds in the more protected areas; all the way to heavy winds with gusts to 35-45 in "The Slot" (the central bay in front of the Golden Gate Bridge). In between the two are areas where wind goes from light to high wind gusts and the boat goes from drifting to heeling heavily while the boat picks up speed. The gusts are controllable with some spilling and/or rounding up and keeping the sails full helps to make headway between the gusts (often times we are also fighting the current).

Don't get me wrong; we are usually reefed down more heavily than other boats on the bay when the wind picks up. However; I would not have my running rigging set up for a potential failure if the wind decided to overpower us before we could get a reef set.

Quote:
8:1?!?! You do realize we're talking about a 30' boat here, right?
{windward sheeting}Don't know what that means, sorry.
It seems experimentation is in order. Chris suggests not sheeting the main in quite so tight and bringing the traveler up, you suggest sheeting the main down tight and lowering the traveler.
Yes; I do. I also realize that the boat is set up with a 2/3 boom sheet and the loads get much higher with that type of control setup. Again; you want your crew to have an easy time working the sheets so fatigue does not set in. That's what 2-speed winches and triple blocks are for. You already know that a 4:1 system is too much working load; why not fix it? Dump the extra line down onto the cabin sole when you are going upwind; so that it is not in the way of your feet and tiller. 6:1 would probably be a good compromise.

Windward Sheeting is a special traveler that Harken makes. It releases the leward cam cleat on each tack so that you only have one control line to release when you want to hike or lower the car. It's an interesting invention; but not really necessary unless you want your controls at the car instead of at the ends of the track. You probably have 4:1 purchase on your traveler and that should be fine for your purposes.

If you loosen the main and hike the traveler you -might- reduce heel; or you might increase draft (power) and become over powered. When we want to go fast in light wind we hike the traveler and ease the main. The small amount of twist at the top is not really an issue for performance; the curvature of the sail down low is what we are looking for. If you flatten the sail you are first going to reduce it's power and then you can lower the traveler car to control it. If you get wind that is too much for this then you can ease the sheet to luff the sail; or reef.

Quote:
I am never going to be trying to sail that boat in 30 kt winds with a full main. By 30 kts I should be on the 2nd reef point and have the #3 up, if anything.
It's not about what you plan; it's about planning for what might be an unplanned situation. That's where you consider "what's the max load that these components will EVER possibly see"? And then you usually double that figure for safety. I'm sure this type of safety factor has been put into your standing rigging; why should it be any less for the controls? Otherwise; it's the life of you and your crew that you are putting in the hands of the weather gods. But we are only talking about what you want for a conservative cruising setup so you can get away with a rated SWL for a gust at 40 kts (IE SWL of 4000 lbs). Harken's sailing-spec calculator recommends these components, the load calculator confirms it; and these calculators were developed by engineers who know what components are suitable for the loading described.


Quote:
Had a chance to look at some Lewmar blocks over the weekend. I must say I'm impressed. They somehow seemed more... substantial (?), is the best way I can think to put it, than the approximate equivalent Harken parts. Also, it looks to me like Lewmar is getting higher safe working and peak loads than Harken in blocks with a smaller footprint.
Does not matter what brand IMHO; so long as the SWL is in the correct range. Please, don't confuse "Breaking Load" with "Peak Load". You never want for the actual "peak" load to be close to the breaking load; because you are only asking for a failure of the component; or premature wear (damage to the bearings, fatigue of the metal, etc).


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I've had Alex say the 60mm Lewmar fiddle blocks should be fine for our needs (SWL: 882 lbs, breaking: 1764 lbs.)...

So I think I'm just going to give the 60mm Lewmar blocks a try, and go from there. That seems about mid-way between the two extremes of opinion . Besides: The Admiral won't let me spend over $400 on the 80mm Lewmar solution.
Hmm... I think you should be making the decision based on what the calculator tells you and erring on the side of safety. At 25 kts wind your mainsheet bail will see a load of 1500 lbs; so that is way too close to the breaking load of 1760 lbs. Certainly 25kts wind is within the normal cruising range for most boats; your apparent wind in 15 kts true is over 20kts. Personally I would want components that are failure-proof instead of failure-prone. Does The Admiral have a good life jacket? She should consider the mainsheet control just as important to her safety as a good PFD.

Last edited by KeelHaulin; 09-24-2007 at 03:22 PM.
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