A Golf Lesson on Plumb-bobbing

Putting isn't just about feel. It's also about information processing. In other words, the better you are at reading greens, the more likely you are to sink a putt. You don't need a golf tip to tell you that. Plumb-bobbing is an old-school technique for generating information that's useful in putting. Some players swear by it. Others disregard it. The question is can it help you sink a putt.

The biggest knock against plumb-bobbing is that it tells you how a putt breaks but not how much. But a computer model developed by Fredrick Haney, Ph.D., a few years ago, is changing the way golfers think about plumb-bobbing. Haney's model suggests that there's more to it than meets the eye and that with a little effort you can use it to help determine how much a putt breaks. Improve your putting and you'll slice strokes off your golf handicap quickly.

The Art of Plumb-bobbing

Before we get into Haney's findings, lets take a look at plumb-bobbing and how to do it correctly. Here are six tips on plumb-bobbing:

1. Stand behind the ball
2. Extend one arm
3. Hold the grip lightly
4. Align your dominant eye
5. Flex your knees
6. Align the shaft's longest point

Stand behind the ball so the hole, ball, and your dominant eye are aligned. Keep your eyes parallel to whatever slope exists on the portion of the green you're standing on. Flex your knees slightly. Let your body tilt with the green's slope. Holding the top of the grip lightly between your thumb and forefinger, extend your arm slightly. Let the putter hang freely in your grip.

Next, using your dominant eye, line up the putter so that the shaft's lowest point covers the ball. Without moving your head, look up at the hole. If it appears to the right of the shaft, the hole slopes left. If it appears on the left, the hole slopes right. If it's in line with the putter, the hole is flat. That's all there is to it. You could learn all you need to know about plumb-bobbing in the first 5 minutes of a golf lesson.

Determining Plumb-Bobbing Distance

If you plumb-bob correctly, you'll notice that the putter makes a point either left or right of the hole on the putting surface. The distance from that spot to the center of the hole, Haney explains, is the plumb-bob distance (PBD), a measure of slope and distance at the ball. On a level putt with no right or left break, the PBD is zero. But for all other putts, plumb-bobbing produces a discrete value. That value is an indicator of how much the ball will react around the hole.

Using PBD, Haney developed a computer model on plumb-bobbing. It takes into account varying speeds of greens, the distance of a putt, and the amount of slope (both sideways and up or down). It also takes into account the effect of friction on a putt. When you first stroke a ball, it first slides and then rolls. Both are considered in the computer model. The force of friction causes the ball to slow down. Haney's goal was to figure out if you could use plumb-bobbin to determine the true amount of the break.

Computer Model Guidelines

After examining lots of examples and producing numerous charts, Haney concludes that for typical green speeds (9 on the Stimpmeter) and level putts (no uphill or downhill slope), the amount of break varies from slightly more that the PDB for gentle slopes to about 1-1/2 times the PBD for steeper slopes.

The above guidelines assume you're following the Dave Pelz suggestion for leaving your missed putts 17 inches past the cup. If you like to die your putts into the hole, then you need to allow for about 2 to 4 times the PBD for steeper slopes.

For similar conditions, moderate uphill putts break as little as half the PBD. Down hill putts can break anywhere from eight to 10 times the PBD. Obviously, downhill putts break much more than uphill putts. Green speed has much the same effect as uphill and downhill putts. The break is greater for faster greens than for slower ones.

Putting is about feel and information processing. The better feel you have and the more accurate your information processing, the more your chance of being the kind of putter that sports a low golf handicap and that I talk about in my golf tips. Keep in mind, however, that there's no magic formula for determining the break on a putt. But by experimenting and using PBD as an additional bit of information, you can improve your green-reading skills.