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  1. #21
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    Quote Originally Posted by corptaxman View Post
    I'm sure it does work for you, in that it can give you a speed number that you can compare to a bowl you roll elsewhere - but, what I'm saying, is : does it give a result that would be comparable to the one that I, or anyone else, would get? A chute or Stimpmeter should give an absolute number for the green at that time that anyone can relate to. Anything that stems directly from a fallible, variable human input cannot be relied upon to do that.
    My calculation if rounded up to the nearest whole number gave me 19, Dales with the chute came up to 19.1 near enough for me.I thinki am correct in saying that in Melbourne before state matches they use a method similar to mine ,ie they do not launch the bowl27 metres, but have a conversion chart for time and distance,to speed . A stimpmeter gives the speed on a flat part of the green, not to many greens are flat are they.
    No Grey Areas

  2. #22
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    John,

    The CG's in Gold Coast were my first exposure to the Australian Small chute. You are correct in the fact that it is time taken to travel over a small distance at various places on green and there was a conversion chart! This used very small bowls. This method gave similar results to the traditional (and used) method of timing to a 27m Jack.

    Notice you still have not answered my question to you, 10m in 14 secs how is your bowl going to travel 17m in 5.2 secs on your 19,2 sec green !!!

    Had you said 14m in 10 secs it would have been understandable as assuming same average speed it would go 28m in 20 secs which is comparable to 27m in 19.2 secs.

    This is my final comment on this thread

    Correct formula to get to a time for 27m Jack mathematically assuming same average speed throughout is

    27 / (straight line distance travelled in metres / time taken to travel said distance in seconds)

    This formula works for any combination

    14m in 10.0 secs = circa 19.2 sec green
    10m in 14.0 secs = circa 37.8 sec green !!! Very good luck on this green
    10m in 10.0 secs = circa 27.0 sec green !!! Just good luck on this green
    20m in 15.0 secs = circa 18.7 sec green
    27m in 13.5 secs = circa 13.5 sec green
    30m in 10.0 secs = circa 9.0 sec green
    33m in 11.0 secs = circa 9.0 sec green


    Hope this puts to an end any disputes on my method of calculation being correct to provide an approximation of average green speed based on distance travelled in a measured time
    Commonwealth Games Technical Official - Glasgow 2014, Gold Coast 2018
    Glasgow Bowling Association (GBA) President 2018

    Any views stated on here are my personal views and do not represent the views of any association I am a member of

  3. #23
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    "A stimpmeter gives the speed on a flat part of the green, not to many greens are flat are they."

    That is correct, especially on modern greens, although there is generally sufficient to allow the test to be run. Modern Stimpmeters seek to allow for that as far as possible by having two grooves/notches, one on either side - the first is the standard notch distance and can be read directly: the second, on the other side, is closer to the end so that the ball does not roll as far off the chute (and thus requiring a shorter flat distance to be found) - it's 'reading' is multiplied by 2 to get the Stimp speed. You are meant to roll in both directions and take an average to reflect the lie of the grass.

    Nothing will be perfect in this respect, and in the case of golf greens the true effective speed of a green as perceived by the golfer will take account of the changes in gradient which he will experience amongst other things (wind for example - even quite light winds can make a big difference, especially on a seaside links).

    At the end of the day, I would rather rely on something like a Stimpmeter chute, purely because it does apply a fairly standard known rate of acceleration*: being operated by gravity (which dictates that objects fall to earth at a speed of 9.8 m/sec.squared) - not the arm of a human (which applies an unmeasured and potentially variable rate between 'goes') . You have never commented on this aspect of matters, despite my mentioning it several times. It also takes out of account the difficult-to-ascertain precise moment that the object leaves the hand (in the case of a bowl) - the end of the Stimpmeter/chute does not move, unlike the hand. These factors are no doubt why firms use a chute to measure the speed of a carpet - and not have one of their operatives, no doubt panting from all that effort, throw a bowl down it as soon as he has finished work! If doing it by 'hand' is just as valid, why do they bother to buy/use a chute? You can treat that as a rhetorical question, as I think I, and most folk, can guess the answer to it!

    * although even that can vary: one of Newton's Laws is that Force = Mass x Acceleration. If you vary the mass (here the weight of the bowl being used), but keep the same acceleration, the effective force applied will change. So, my 'measuring' green speed using my heaviest size 6 bowl (1.6kg) will surely produce a different result to someone using a size 2 lighter-weight bowl (unless they can apply a just-sufficient different degree of acceleration to precisely compensate - which isn't going to happen in an ad hoc roll).

  4. #24
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    Quote Originally Posted by corptaxman View Post
    "A stimpmeter gives the speed on a flat part of the green, not to many greens are flat are they."

    That is correct, especially on modern greens, although there is generally sufficient to allow the test to be run. Modern Stimpmeters seek to allow for that as far as possible by having two grooves/notches, one on either side - the first is the standard notch distance and can be read directly: the second, on the other side, is closer to the end so that the ball does not roll as far off the chute (and thus requiring a shorter flat distance to be found) - it's 'reading' is multiplied by 2 to get the Stimp speed. You are meant to roll in both directions and take an average to reflect the lie of the grass.

    Nothing will be perfect in this respect, and in the case of golf greens the true effective speed of a green as perceived by the golfer will take account of the changes in gradient which he will experience amongst other things (wind for example - even quite light winds can make a big difference, especially on a seaside links).

    At the end of the day, I would rather rely on something like a Stimpmeter chute, purely because it does apply a fairly standard known rate of acceleration*: being operated by gravity (which dictates that objects fall to earth at a speed of 9.8 m/sec.squared) - not the arm of a human (which applies an unmeasured and potentially variable rate between 'goes') . You have never commented on this aspect of matters, despite my mentioning it several times. It also takes out of account the difficult-to-ascertain precise moment that the object leaves the hand (in the case of a bowl) - the end of the Stimpmeter/chute does not move, unlike the hand. These factors are no doubt why firms use a chute to measure the speed of a carpet - and not have one of their operatives, no doubt panting from all that effort, throw a bowl down it as soon as he has finished work! If doing it by 'hand' is just as valid, why do they bother to buy/use a chute? You can treat that as a rhetorical question, as I think I, and most folk, can guess the answer to it!

    * although even that can vary: one of Newton's Laws is that Force = Mass x Acceleration. If you vary the mass (here the weight of the bowl being used), but keep the same acceleration, the effective force applied will change. So, my 'measuring' green speed using my heaviest size 6 bowl (1.6kg) will surely produce a different result to someone using a size 2 lighter-weight bowl (unless they can apply a just-sufficient different degree of acceleration to precisely compensate - which isn't going to happen in an ad hoc roll).
    I f that is what you think fine, i have had enough willonly in future talk. About the laws of the game,
    No Grey Areas

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