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Old 2nd September 2006, 04:06 AM   #4
Roger
Dream Team - School Guru
 
Join Date: Aug 2006
Posts: 2,092
Default RE: Harness and Footstraps

Hi Tom,
First, I think we need a little more information to get the full picture here.
What size rig are you using on your Carve 145?
How much windspeed (an estimate) are you sailing in.
Here's a few things to try for starters, until we get more info to see the
overall situation more clearly:
First, since you are so tall, you may want to either have a good sail loft move the boom cutout up higher in your sail (s).
Before you do that, it might be good to experiment by putting a couple of inches more extension under the bottom of your sail.
It's not real good rigging practice, but it will allow you to move the boom up a good 2 inches to see if that helps with getting your weight on the harness. If so, then have the boom cutout in your sails moved up a few inches.
I see from your original post that not being able to put weight on your front foot is an issue for you.
Putting weight on your front foot is most likely WHY your board tends to turn upwind.
Any weight , that far off center, is going to tip the upwind rail down and cause your board to immediately want to turn upwind.
As far as getting so far back you are sinking the tail of your board, you are probably going for the rear footstrap (s) way to soon, before your board has developed enough speed to support you back that far.
Let's look at the different stages here and also the physics.
When you uphaul, your feet are spaced one in front, and one behind the mast base.
Then you move back unitl your front foot is 4-6" behind the mast base, 4-6" upwind of the centerline, and toes pointing basically forward.
Your rear foot is about the width of your shoulders behind the front foot and you place your rear heel right on the centerline of your board.
If place both feet, behind the mast, as suggested above, you can then bring your rig across the board (in front of your front shoulder) and begin to sheet in by rotating your upper body (relative to your feet.
Rotate your upper body and the rig a few degrees (5-10 deg. max here) to get underway. A line drawn from your front shoulder to your back shoulder will need to stay parallel to a line drawn from the center of the boom head to the center of the tail of the boom/clew of your sail.
So, you can say that your shoulders pretty much always are parallel to the fore/aft centerline of your rig.
OK, after you sheet in your board will begin to move off on a beam reach. It will gather some speed. As it gains speed, you can begin to move back on your board , keeping your shoulders parallel to the centerline of the rig. Sheet in a little more to gain some more speed and begin to move your feet back on the board, progressively, as your speed increases. Try to keep your board accelerating. If you don't move back at the same rate, the board will stop accelerating.
If you move back too quickly, your board will stop accelerating.
Keeping the board in constant "acceleration" is the key here.
When you get your back foot back behind the front footstraps (I can't tell you exactly where as I'm not 6' 7" tall nor do I weigh 95 Kg.) place the arch of your rear foot directly over the fore/aft centerline of your board.
Try different positioning (fore and aft) until you find the sweet spot where the front of the bord lifts in a manner that keeps the board accelerating and brings the waterline length back until the "bow wave" of your board is back between the mast foot and the front footstraps.
This was the first "physics" lesson. Gotta get the nose of the board up and the planing surface at the back of the board inclined correctly so your board will want to climb up over it's bow wave and begin to plane.
Pure physics here! If the nose stays down, the board won't plane.
If the nose "pops up" too high, the tail of the board will drag and you won't plane for the opposite reason. Find that sweet spot where the board just continues to accelerate, going faster and faster.
Try to keep the board really flat on the water. If you need to "steer",
toe pressure on your back foot turns you off the wind, and heel pressure on your back foot turns you upwind. Your feet should still be about shoulder width apart, and you should still have your shoulders parallel to the f/a centerline of your rig.
Now either pull the sail closer and hook in to your harness line, or put your front foot into the front footstrap. Some sailors like the security of being in the front footstrap, some like the feeling of being hooked in. Either way works, so it doesn't matter.
Now for the "2nd Physics lesson".
Before the board can really accelerate to full speed, you need to get your weight off the board (yes, I mean totally unweight the back of your board). So where can you "attach" your weight to get it off the back of the board.
There's only one place! You have to hook in (if you haven't already) and begin to transfer all your weight off your feet and onto the rig, through the harness line, the boom, and then down to the board at the mast foot. Mast foot pressure will continue to push the board forward and keep it accelerating, but you have to get fully hooked in and have enough speed for the board to support you before mast foot pressure can "push the nose" over onto a full plane.
Now that you have virtually no weight on your feet since you are "hooked in" and the board is being driven by mast foot pressure, you can put your front foot in the front footstrap (if you havent already done this) and apply all of your weight to the harness line and rig.
Now you can easily slide your back foot out and into the rear footstrap.
Pump a little with your back foot to accelerate your board even more.
Then sheet the sail full down and in and rake it back fully.
Until you are really fully planing the rig will never be raked back fully, nor will you be sheeted in fully. As you are moving back, getting hooked in, and finding the footstraps, you will be progressively raking the rig back slightly and sheeting it in slightly as your upper body and shoulders turn with the rig. Until you are fully planing, your sheeting angle will probably not be < 45 deg. off the boards F/A centerline.
When it&#39;s sheeted out at around 45 deg. it makes max. forward drive.
As your board accelerated to full speed, you get increasingly more apparent wind, and with the increase in apparent wind you can sheet in a little more without destroying the forward drive and turning it into leeway making sideways force.
Hope this helps,
Roger is offline   Reply With Quote