I've been coaching novice helms and trying to get the settings right on my boat. Also noting Shaggy's comments on the Pogo in other thread.
It seems like the groove on my boat is super narrow. I think we're pinching too often.
There's only a touch of weather helm but it's my firm belief that the mast has too much rake in the neutral position.
What ways are there to get a more positive "groove" when the boat is on the wind? Slot wider or tighter? I can bring the sheeting angle in also.
all other things equal, does a more upright mast mean a narrower slot?
Also, I have the B&G analogue wind which is super-responsive and the apparent measurement (not derived) is pretty accurate. Should I be using that in addition to tell-tales and in preference to the windex?
I am not sure what you mean by a narrow groove. In my experience there is no such thing. The boat will have a groove that you decide. You can go high mode - which is when you pull sheets on a little and go for pointing, vmg - both telltales flowing and low groove - to get her rolling along. Each mode requires adjustments in sheet tension and maybe traveller and vang. There is an ability to have a narrow groove to windward if your genoa is built with a very fine entry. For cruising a headsail should be more rounded in the luff so that it is easier to sail to.
What boat and what exactly is the problem?
Bringing the draft or camber in the sail forward usually helps the helm along with adding more twist especially in rough conditions when the boat is being tossed around,,, it ensures that some part of the sail has the correct angle of attack at any given time.
Draft aft gives a finer angle of attack to apparent wind , points higher but harder to steer .
Select to expand quoteJolene said..
Bringing the draft or camber in the sail forward usually helps the helm along with adding more twist especially in rough conditions when the boat is being tossed around,,, it ensures that some part of the sail has the correct angle of attack at any given time.
Draft aft gives a finer angle of attack to apparent wind , points higher but harder to steer .
This is it I think! I've started taking pictures upward from the deck. I reckon we've been oversheeted with the draft too far back. I'm going to try to bring the sheeting angle in to let us ease the sheet a little And get more camber, further forward.
To widen the groove, the standard moves are;
1- More twist in the main and jib;
2- Move jib draft forward with extra halyard tension;
3- Ease runners or topmast backstay to increase headsail sag, increasing depth and moving it forward (but ensure that both jib and main are still twisting enough as this will tend to close the head on both sails);
4- Ease jib sheet to induce depth and twist, and (if you have an athwartships control) consider moving it out to sail low and fast with better flow over the keel. You may lose height theoretically, but maintain it because the boat isn't stopping when it's out of the groove;
5- Less mainsheet to induce twist and to work with the eased jib;
7- sometimes increase heel to give more feel if the boat really needs it, but flatter is normally better.
if you've got a swept-back spreader fractional rig without runners, tuning the stay and forestay tension to allow the forestay to sag and give the headsail extra forward draft in light winds can be critical.
Fair to say that increased sag in the headsail by loosening tension in forestay less of a thing when the headsail luff is in a furler foil on the forestay?
OK so this thread gets better and better. Chris your points 2 and 3 are borne out by the below:
i put the photos i took of my jib before and after pulling the backstay on through a program that calculates the curve.
Without backstay (more headsail luff tension more forestay sag) the deepest curve was at 38% - probably where I want it.
with the backstay on the deepest curve was at 44% - a huge difference, and contrary to my belief, backstay doesn't automatically make us point better.
Select to expand quoteQuixotic said..
Fair to say that increased sag in the headsail by loosening tension in forestay less of a thing when the headsail luff is in a furler foil on the forestay?
IMHO the presence of a furler mainly affects three things;
1 - the effect of the extra weight may cause more sag, but that's probably very minor;
2 - most sails on furlers are probably more cruise-oriented and therefore will stretch more than laminate race-style sails and therefore may need more variation in luff sag;
3 - whether the furler gives a rounder and more forgiving entry to the sail, or whether it obstructs the flow over the luff and makes it less forgiving, makes my head hurt.
4- How important it is depends on the overlap of the sail. A bigger overlap sail is less responsive to forestay sag and it's also more likely you'll be changing to a smaller sail or reefing. A modern short-overlap rig can give a much wider range with one sail unrolled to maximum extent, so it's important to be able to optimise the depth since you don't change the area.
I've got a black cruise laminate No. 1 on a furler and find that stay tension is still very important. Only by tightening the rig to create a tighter forestay when under max. backstay could I flatten the sail to get the required depth. If I ease the backstay in a breeze it looks horribly deep and goes slow.
PS - this information comes from conversations and sailing with top sailmakers years ago but it still seems to be OK.
