dunedin
Well-Known Member
Not sure there is much stretch in a rod forestay compared to the sail and the halyard.
Kind of interested - does the adjusting have the same degree of effect with furler as non-furler??? I've always had furlers so never done the adjustment of the halyard.. I whack it up in the spring, tension it, and it stays that way until the autumn..
That's all correct. But it's not cruising boats that are less sensitive, it's the way people sail them. Setting up with a flat entry, for pointing (as you describe correctly) gives you a narrow "groove" to steer in. You can point a bit higher in the right conditions (flat water, not yet overpowered) but you really have to concentrate. If you are 2 Deg below your course, you stall the jib very quickly.yes - it has the same effect.., except for the "scalloping" that i mentioned in the post you quoted - that is somewhat affected by the presence of a foil.
basically there are three setups:
1) hank-on.., 2) foil but no furler (common on bigger race boats) 3) foil and furler (cruising boats and one-design race boats - e.g. J/70)
on all of them, the jib halyard tension can be used to control the draft position of the sail.
I understand that some large cruising boats may not be particularly sensitive to this kind of adjustment, and it might not be worth the effort for some.
but for me, even when i am out for a daysail.., i can't help myself - I give the tiller to my wife, and I run around tweaking everything.
even on a big cruising boat.., if, say, the breeze is light and you have a quite high halyard tension, you might be giving up some pointing ability. Having too much halyard tension for the conditions puts the draft too far forward, giving a very blunt entry - as you come up on the breeze the jib will luff early. reducing the halyard tension will give a finer entry by moving the draft aft, and you may be able to come up a few more degrees on the wind before the sail luffs.
That's all correct. But it's not cruising boats that are less sensitive, it's the way people sail them. Setting up with a flat entry, for pointing (as you describe correctly) gives you a narrow "groove" to steer in. You can point a bit higher in the right conditions (flat water, not yet overpowered) but you really have to concentrate. If you are 2 Deg below your course, you stall the jib very quickly.
A rounder section gives you a broad groove. Better in waves and gusts; also better if you don't feel like concentrating too much or have the autopilot on.
I am well aware of draft and so on ... having raced and successfully ... but with a furling gear groove - I find it hard to imagine I can get same amount of effect as with a hanked on sail.
Anyway - the OP IMHO was not asking in relation to draft / racing or similar ... I get impression he was asking in regard to CHECKING and re-tensioning if halyard etc. stretches.
I don't think that's strictly correct either. Sorry to be anal but the question is not fractional Vs masthead, it's "where does the forestay tension come from; how much is it adjusted while sailing and is that before/ after the halyard is set".
If you start with swept-back spreaders and a pre-bent mast, correctly set, your initial forestay tension comes (we agree) from the shrouds; the backstay then adds more. If instead you have inline spreaders then it comes from the runners, and my concern about halyard tension would then apply to your runner settings: apply max halyard with runners on, not off. On this type of rig it's not that the runners have a different effect, it's that when you let them off downwind the forestay might be flapping around; the range of travel is greater.
With masthead rig and in-line spreaders, all the forestay directly comes from the backstay. And then you can tighten it a bit more. On some cruising boats the mast is damn stiff and the backstay is just wound on and left; it's certainly never as loose as you might leave it on a 19/20 rig or the mast would be wobbling around.
So in all cases, if you're going to adjust the forestay tension under way, it will come from somewhere. If you do it with the jib up, it will affect the jib luff and halyard. A bit, depending on (1) how much you move the mast and (2) how much you've grown the span of the forestay in tensioning it; depending also (3) on the stretch of the forestay relative to the sail and halyard. Whether that bit is meaningful is a matter of degree; if I have set max halyard, I personally am very intolerant of another 5-10mm of stretch.
How much did I indicate and how much actually is it?My point has always been that the backstay is doing less than you seem to indicate for forestay sag on a fractional rig. Note that grand prix yachts with twin backstays are now using deflectors mounted at forestay height to transfer backstay load more directly to the forestay to help reduce forestay sag. Forestay rams are now standard at the top end as well.
Well you indicate that it's enough to manifestly influence halyard tension, and I don't think it is.... Especially with a rig with plenty of pre-bend.How much did I indicate and how much actually is it?
I'm not familiar with the deflectors you speak of.
Well this has been interesting and I suggest we wrap it up for now. Thanks for the info on deflectors.Well you indicate that it's enough to manifestly influence halyard tension, and I don't think it is.... Especially with a rig with plenty of pre-bend.