## Description

This article is from the Lefthanders FAQ, by Barry D. Benowitz b.benowitz@telesciences.com with numerous contributions by others.

# 10. What makes a bowling ball left or right-handed?

Left-handed bowling balls are different in two respects.
The first, and most obvious, is the placing of the finger holes
in relation to the thumb hole. What follows is the first (and
last) square bowling ball you'll ever see <G>:

```		0			0
0                 0
+                     +

0                     0
```

The view is from the top and the spacing is highly exaggerated.
Mark Hideo Fujimoto <fuj@uclink.berkeley.edu> points out that
while this configuration is true for a vast majority of people,
one cannot say it is true in the general case.

The ring finger is held behind the middle finger, as it is then
the last thing to leave the ball - imparting spin. Using a right-
-handed ball, the middle finger, or the thumb, would be last.
Neither of these digits will impart any spin at all to the ball.
Spin is important to make the ball curve, or hook, into the pins
and the rotation of the ball stabilizes it as it drives through.

The second consideration, which I cannot draw (do I hear cheers?)
is the location of the center weight with relationship to the spot
where the holes are drilled. The ball is drilled so that the weight
is slightly ahead of the thumb hole and to one side - left, for
left-handers. This balancing weight provides extra momentum and
spin to the ball.

Mark Hideo Fujimoto <fuj@uclink.berkeley.edu> disagrees:
I have to disagree here, too. The "center weight", or more correctly,
the center of gravity of the weight block, is usually placed to the
*left* of the (+) in my diagram for a left-handed ball. This is known
as "positive weight", which combined with lift and spin imparted by the
bowler, gives the ball a more pronounced hook than a ball without this
type of weighting. Once again, this isn't the only way to drill
a bowling ball, but it is one that tends to be conducive to getting the
ball reaction that produces more strikes.There will be times when other
types of weighting will prove to be more beneficial than "positive"
weights.

Throwing the ball fairly normally for a beginner, one should
ideally see some clockwise rotation as the ball tends to drift
toward the center (a strike!). Throwing a right-handed ball with
your left hand places the weighting on the left side - meaning the
ball will go straight, or even back up (a reverse curve). This
kind of delivery makes it almost impossible to get the ball to the
center with force and momentum, unless you are a 300-pound gorilla.

Mark Hideo Fujimoto <fuj@uclink.berkeley.edu> clarifies:
you don't have to be a "300lb gorilla" in order to overcome the effects
of various ball weightings. If a left-hander imparts a clockwise ro-
tation to the ball, regardless of whether it's a right-handed or left-
handed ball, the ball will hook from left to right. The weights may
alter the way the ball hooks (i.e., earlier, later, stronger, weaker.),
but not the direction in which it hooks. Many bowlers use "negative
weight" (placing the weight block's CG closer to where the ball rolls)
in order to reduce the amount of hook on lanes that promote hook (i.e.
"dry" lanes, lanes with little oil on them).

Most bowling establishments have a couple of left-handed balls
for use. These are usually in poor shape, but a lot better than
trying a right-handed ball, for the reasons stated above.

The good news is - a left-handed ball, drilled by a professional,
costs EXACTLY the same as the right-handed one. And, to spur your
confidence, don't forget that the first man to earn a million dollars
in bowling, Earl Anthony, is left-handed.

Thanks to: Bob Snyder <snyderr@buffnet.net>
Mark Hideo Fujimoto <fuj@uclink.berkeley.edu>

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