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I How to mark a "measles ball" for practicing Snooker spin

  1. Nov 28, 2017 #1
    Please excuse me if it's not appropriate to post this question here, but since this group has knowledge of both math and snooker....

    I'm wanting to make my own "measles ball" for practicing spin on the cue ball. These are cue balls with 6 dots perfectly/evenly spaced on the ball so you can see which direction and how much it is spinning.

    Question is: what is the simplest way to figure out where to place each dot should be drawn?

    The reason I don't just buy one is that they don't seem to be available for American Snooker (2 1/8" ball).

  2. jcsd
  3. Nov 28, 2017 #2
    By the way, I know there are algorithms for placing N equidistant points on a sphere, but what I'm looking for would be instructions on a more practical level like, "draw the first spot, then position the ball so that...."

    It's really not that important to me that it be exactly 6 spots, if there's a much simpler way to do this by changing the number, but 6 spots seem to be the standard for some reason. I also have a laser level that I could use to shine 90 degree lines down (cross) on the ball if that would help.
  4. Nov 28, 2017 #3

    Vanadium 50

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    At the centers of the faces of the circumscribed cube. (Or equivalently, at the vertices of the inscribed octahedron)
  5. Nov 28, 2017 #4
    Make a 2 1/8" sided box and drill holes in each face. Place ball in box... Alternatively use proper sized balls.

  6. Nov 28, 2017 #5
    Exactly - thanks for the help (correct me if I'm wrong, but for American Snooker, 2 1/8 balls are used)
  7. Nov 28, 2017 #6
    I didn't know there was such a thing as American Snooker, it's sacrilegious :-)

  8. Nov 28, 2017 #7
    Yes, I'm sure 99% of people in the UK would feel that way. Pool is a great game, but I really wish snooker would catch on more in the US.

    I have a 10' American Snooker table in my den, and that's the only game my young nephews saw for several years. When they first saw a pool table at a family reunion, the balls and pockets seemed so big that they said, "is this real?"

    I'm sure a 12' UK snooker table would be even more challenging, with the 2 1/15 balls and tiny pockets.
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