Gestalt said..
Hi Chris,
Being very much in the heavyweight camp i've used a few boards that were too flat and nose dived all the time. Only thing I could do was move the mast back and that just kills the upwind.
This board the nose sits just above the chop. Feels really good so far.
I'd love to get your experience with setup. Peter N has been helping me tweak the board and rig. I need a few more fun races to keep dialling things in.
I seem to have some ok downwind speed but need to move my mast forward a cm or so to get a bit better performance upwind. I'm finding upwind the board is stalling a little when I push really high.
Once I get it dialled I"ll paint mark everything.
At around 77-78kg, my mast foot is positioned around 9cm from the back of the track. It moves forward only when I've already been catapulted a few times, or when you have to duck oysters being blown off rocks when rigging. When it's completely survival conditions the mast base can go slightly ahead of halfway, but that is rare.
Upwind pace with the mast well back is normally pretty good. One thing is that when it's breezy, you are really leaning the rig to windward, sailing on shortened harness straps and with the centreboard raked back so that the adjustment arm (or whatever you call the bit you kick to move the CB) is vertical, and of course you're railing the board. Having the rig aft and board aft allows you to move your weight back to get the bow to lift.
Stu Gilbert apparently likes flat boards because in a big breeze they can act as wave piercers, but he's also enormously experienced and has the handling skills you'd expect of a four time world champ.
As far as rig setup goes, I think most of us in the heavier end of the mediums or the lighter end of heavies (ie guys like Dennis, Stu and me) all tend to set up with fairly light downhaul tension in light or moderate winds. Most of the time we have horizontal wrinkles coming off the luff and extending back maybe 10". This is because we are using quite light downhaul tension, which means the mast does not bend as much and the sail takes up a fuller, draft-aft shape. I tend to use a fairly tight outhaul (I'll get some measurements next time I sail) to keep the leach tight so that I can point. This setup is partly because I tend to struggle to get height on boards in medium and light winds, although oddly enough in Lasers (and sometimes in Tasars) I had excellent light wind height.
As noted, there is a fair bit of variation, and the lighter guys and gals tend to sail with much flatter rigs, while some quite light mediums like Dave West can go very well with lots of depth; I've got a limited range of tune because I sail so many other classes (Lasers, Tasars, yachts, and fast cats, etc) that I don't have the fine feel for speed of other guys like Dennis, who can get anything to go fast.