Potting a ball on the cushion - imparted spin?

[Touchwood]

When I were but a lad I was taught that when attempting to pot a ball on a cushion it helped to put running side on the cue ball - that is, if striking the object ball on the left, right hand side. The idea was that the spin was imparted to the object ball and helped it to stay on the cushion.

I now understand that the above theory has been disproven, by using marked balls and slow motion photography (though I can't track down the evidence) This makes sense to me, and was in fact suggested to be the case by the great Joe Davis many years ago.

So does it really help to impart spin in this circumstance, and if so why?

My experience is that it DOES help - I certainly pot more balls along the cushion if I do use spin than if I don't.

Joe suggested that the cue ball travels in a slight curve, and strikes the object ball nearer to full ball in line with the pocket - but that seems to me unlikely.

I'm wondering if the fact that the cue ball is spinning makes it run along the cushion slightly as it strikes the object ball, towards the pocket, thus pushing the object ball in the right direction (not easy to explain without pictures)

Anyone got any thoughts on this?

[Touchwood]

Hmm - think I mean check side, not running side - no edit available on this forum?

[DeanH]

there is an edit function but may only appear when you get more than 10 posts.

There is a post from TheLongBomber (IIRC) with a video of this being demonstrated.

[vmax4steve]

I'm wondering if the fact that the cue ball is spinning makes it run along the cushion slightly as it strikes the object ball, towards the pocket, thus pushing the object ball in the right direction (not easy to explain without pictures)

You are quite correct and this is indeed the reason why balls are easier to pot along the cushion using running side not check.
If the cue ball strikes the cushion slightly before contacting the object ball it will hug the cushion for a very short distance and make contact with the correct contact point on the object ball, if it strikes both cushion and object ball simultaneously then the correct contact point on the object ball is also contacted.
Playing these shots with running side gives you a greater target area to hit ie: just before the object ball or at the junction of cushion and object ball.

Joe was also right in that the cue ball does travel in a slight curve, but this is not the reason for making the pot, it's the reason why this slight curve has to be allowed for when playing this shot so the shot needs to be practised, it's not an automatic given that the ball will be potted just because running side is on the cue ball.

[Terry Davidson]

vmax has it correct. You don't need a ton of running side which I see a lot of players doing, just a touch and no more than one tip width off centre so that the aim doesn't have to be adjusted too much to compensate for throw

Terry

[Touchwood]

Many thanks for that, Steve/Terry.

Nice to have one's theories confirmed.

I wonder if you can also confirm my theory that there is a little invisible goblin who lives in my club that hides in the pocket and stops me potting the black? I've tried placating him with gifts of pork scratchings but the guy that brushes the tables got all upset and threatened to ban me.

[billabong]

A guy in our team once claimed he missed the black ( at pool ! ) because the new black ball was too shiney,
and that he couldn't see his potting angle on it . . .

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