I've probably seen it happen a million times, heard commentators say it during pro matches, but what is the exact definition of "object ball skid".
"Skid" is also known as "cling" or "kick." A detailed explanation and numerous video demonstrations can be found on the cling/skid/kick resource page.I've probably seen it happen a million times, heard commentators say it during pro matches, but what is the exact definition of "object ball skid".
I've probably seen it happen a million times, heard commentators say it during pro matches, but what is the exact definition of "object ball skid".
For a demonstration of how big of an effect different surface conditions can have, see the following videos:It's when the object ball does not follow a normal, predictable path. It usually happens when some type of dirty substance increases the friction between the cueball and object ball.
It might seem like this at times, but the balls don't actually stay in contact any longer when there is cling/skid/kick. What is different is the friction force between the balls during the contact time. It is greater when there is cling/skid/kick.They tend to cling together for a fraction of a second longer than normal
It's when the object ball does not follow a normal, predictable path.
ONB
On a straight shot, the object ball will be predictable....it will go in the pocket.
....but if you are using follow for position, the cue ball may stop dead.
Under the condition you just described, does the OB or CB jump or hop?
For those interested in seeing this in super-slow motion, the following video covers this topic:On a straight shot, the object ball will be predictable....it will go in the pocket.
....but if you are using follow for position, the cue ball may stop dead.
For those interested in seeing this in super-slow motion, the following video covers this topic:
HSV B.46 - CB and OB hop and spin transfer during follow shots
Enjoy,
Dave
Only to the extent that the difference in cloth causes the balls to be dirtier and in particular to have more chalk on them. I suppose fuzzy nappy cloth could be better at keeping the balls clean.... Is tight cloth another contributing factor?
Are you sure "pixie dust" didn't have something to do with it?On the other hand, I remember one disastrous skid a former World Champion had and he didn't blame the cloth or the balls or the chalk or the humidity -- he blamed the brand of table.
Blake,Dr Dave, you have awesome videos that cover just about every aspect of pool. Back when I was in school for engineering, your articles and videos not only inspired me to look deeper into the game, but also inspired me to get into video, and especially, slow motion video.
I've made a couple of videos that aren't nearly as controlled as Dr Dave's, but hopefully still add value in the way of an additional perspective.
One such video has several SloMo skid shots, with the camera on the table, right next to the CB/OB collision.
For these shots, I literally rubbed chalk on the contact point of the OB to purposefully induce skid. You can clearly see the unexpected reaction of both the OB and CB. In these shots, you can literally see the OB hopping a bit off the table right after impact.
You can find the skid shots at about 3:25 in this video:
http://www.youtube.com/watch?v=J2gcgqUt00w
I hope this helps.
Only to the extent that the difference in cloth causes the balls to be dirtier and in particular to have more chalk on them. I suppose fuzzy nappy cloth could be better at keeping the balls clean.
On the other hand, I remember one disastrous skid a former World Champion had and he didn't blame the cloth or the balls or the chalk or the humidity -- he blamed the brand of table.
Excellent point. The black marks might have done that, or they might have reduced the friction at the contact point. If they do either one they make cut shots guess work. I suppose I should have measured the "mark-induced-throw-effect" (MITE) when I had a chance.I remember this to. I believe it was Archer blaming Diamond tables. Diamond tables 100% leave black marks all over the balls. Walk around the tables at DCC and anyone can see it clear as day. (The issue is improved now, but not when Archer made that comment). Would it not be a reasonable theory for a player that these black marks increase the friction between the balls, and therefore increase the chance of a skid?
Only to the extent that the difference in cloth causes the balls to be dirtier and in particular to have more chalk on them. I suppose fuzzy nappy cloth could be better at keeping the balls clean.
On the other hand, I remember one disastrous skid a former World Champion had and he didn't blame the cloth or the balls or the chalk or the humidity -- he blamed the brand of table.
I agree that it seems to happen somewhat randomly. However, any time a chalk mark appears at the contact point between the balls, there is cling/skid/kick every time (100%). I wouldn't call that odd. And when clean surfaces meet at the contact point, there is never cling/skid/kick. That isn't odd either.Skid is such an odd phenomenon, one shot skids and the very next doesn't...