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Thread: Spinout

  1. #1
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    Spinout

    Can someone explaine spinout please.

    Last time round on a 7.3 sail, Gecko 120 board 40cm fin I had no problem. I'm 85kg
    Decided to try a new 36 fin I just bought to see the difference (and to deal better with low tide. Had seriouse spinout issues.
    Interesting that it happened more when I was going upwind and bouncing a bit on chop.

    So how does it work exactly?
    how can you recover?

    Any advice appreciated

  2. #2
    Senior Member Silicon Beach's Avatar
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    So, I'm not going to pretend to give you a scientific explanation, just the 'bog standard' windsurfing one ... spinout is caused by the fin(s) 'cavitating' - that is: bits of air getting around the fin in different ways and disrupting the way the water is flowing over it. In other words: you are pushing against air rather than water, so the fin loses grip, and you go sideways.

    This explains your: "Interesting that it happened more when I was going upwind and bouncing a bit on chop." ... because when you are pushing hard on the fin to go upwind, there's more pressure on it, so you have to be more sensitive with your technique ... and when there's chop there's more chance of air getting under the board and collecting around the fin(s).

    Perhaps when you changed to a smaller fin you needed to improve your technique a bit, and be more sensitive to balancing mast-foot pressure with back-foot fin pressure (try leaning forward a bit more and putting more weight through the harness).

    "
    how can you recover?" ... more or less the same way that you land a jump without spinning out (you do jumps?) ... you pull the tail under your arse with the back foot and push away by straightening the front leg - 'scissoring' the board with your legs ... and in the case of spin out, you slow down a bit, bear off the wind a bit, ease the pressure on the fin etc ... or you just enjoy the feeling of sliding across the water sideways - unless you're travelling at say 50 knots down a speed course ... in which case you may end up in hospital!

    nb other explanations are available, and will, no doubt, be forthcoming.
    Last edited by Silicon Beach; 4th October 2017 at 05:48 PM.
    -----------------------------
    Currently writing the World's first Windsurfing Novel: 'Too Close to the Wind' - watch this space!
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  3. #3
    Quote Originally Posted by AndySG View Post
    Can someone explaine spinout please.

    Last time round on a 7.3 sail, Gecko 120 board 40cm fin I had no problem. I'm 85kg
    Decided to try a new 36 fin I just bought to see the difference (and to deal better with low tide. Had seriouse spinout issues.
    Interesting that it happened more when I was going upwind and bouncing a bit on chop.

    So how does it work exactly?
    how can you recover?

    Any advice appreciated

    Spinnout is very straight forward: You are putting too much sideways load on the fin for the 'lift' it offers. A bigger fin can spinout less – or later – because it offers more lift or more area to push against.

    But don't run back to your bigger fin – another and better solution is to learn to reduce the sideways load on the fin in the first place, and you can do this is several ways:

    1) Try shifting your harness lines back down the boom a bit as that prevents too much back hand load transferring onto the fin via your back leg.
    2) You might also try and shift your weight further forwards on the board, and you can do this by leaning forwards more or perhaps shift the footstrap positions forwards one hole or maybe even two.
    3) A third solution can be to raise your boom a bit, which helps get weight off the tail. Shifting the mast foot back a centimetre can achieve the same thing.
    Last edited by basher; 4th October 2017 at 08:41 PM.
    Now back in the UK.

  4. #4
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    Your original set up sounds a bout right to me...best to keep your 36 for a 6.5/6.6m sail on that board.

    SB covered the bases well...just to add you will get a lot more out of your board if you sail more off the front foot anyway regardless of the fin issue. I suggest you test the balance of pressure on your feet with your existing set up and make sure it enables 60/40 or even 70/30 in favour of front foot. As SB said, also work on getting high upwind without pushing hard against the fin........the freemove/wide freeride boards have neither the tail volume or rail design to make pushing the fin with the back foot a very effective method.

  5. #5
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    Ok thanks Silicon
    But then why does a bigger fin prevent spin out? For sure I was pushing wat more on the 40 cm fin.

  6. #6
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    Spin out occurs when a small amount of air becomes a large vacum. The amount of air getting to the fin + the size of the fin + the side load on the fin all go into the equation. There is a critical point when the cavitation starts / vacum forms.

  7. #7
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    ok I'll stick withj the 40. To be honest it was just an "experiment". And also after using the 36 for a bit I was learning to keep the spinout more in control. I guess I was adjusting myself natyrally without even realizing.
    Agree 36 is a bit small and actually keep that for my 6.6 sail

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