On The Numbers With Doctor Grip

Doctor Grip putting the numbers to use on a True Temper shaft

For the past month the crew of GearEffectGolf has weighed in on a Forum question posed by Janina Jacobs: “Do you really want to know all the launch monitor reveals?”  She wondered whether golfers were getting too caught up in technology, at the expense of athletic “feel.”  Some folks responded that the numbers acquired from a monitor were useful, so long as you understood what to do with them.  Others believe that an average player’s swing on a range is rarely duplicated on a golf course, which renders the data meaningless.

In any event, professional golfers increasingly use launch monitors for feedback on their swings, while pros and amateurs alike rely on the numbers to identify what irons and drivers perform best for the individual.  But according to a study sponsored by Golf magazine, 70 percent of core and avid golfers who bought clubs in the past year did so without even the most cursory fitting.  It’s a fact about golfers and the equipment industry that mystifies and dismays David Butler, a California-based master Miura clubfitter.  Recognized by Golf Digest as one the nation’s best fitters, the man widely known as Doctor Grip was also recently profiled on The A Position.

“I realize not every golfer is interested in custom clubs,” allows Butler, who has made clubs as a hobby and a profession for some 50 years. “I recognize that many employees in golf shops that clear only $50 to $75 on a set either aren’t trained or have incentives to do fittings.  So the average guy who buys clubs does so because he sees them on some magazine’s ‘hot list,’ the new design looks attractive, and the staff tells him that lots of other golfers are buying the same thing.  And when his game doesn’t improve, he buys a different set in a year or two.”

The turnover is good for the industry, not so much for player pocketbooks.

Still, club manufacturers are rightly proud of their brands and popular new designs.  But as Butler points out, most of the products are assembled in China, where quality tolerances might not be as consistent as, say, at a Bavarian auto factory.  What’s more, since few of the shafts in a set have identical flexes and kick points, one club will perform differently than the next.

Butler naturally recommends custom fitting.  But in an exclusive GEG interview, he reveals how a club-buyer with access to the launch monitors and a strike boards found in many golf shops can glean a basic analysis of what driver or set of irons is best for that individual swing.  But first, a few words about the launch monitor:

These wondrous machines use Doppler radar to reveal swing speed, the velocity at which the ball departs when hit, how much reverse spin the club is imparting on the ball, its launch angle and the trajectory on which the ball comes down.  A system like the TrackMan also shows carry, roll, total distance and how much the shot strays from center.  It can also reveal the all-important “smash factor,” which is a measure of the effectiveness of the head and especially the shaft, which Butler calls “the engine of the golf club.”

Balls actually depart at a velocity that exceeds clubhead speed.  Divide ball speed by clubhead speed and you get a smash factor ratio.  A 1.1 or 1.2 represents a poor transfer of energy, while a 1.5 is close to perfection. As GEG readers will recall from a Dave Gould interview with precision clubfitter Brian Anderson, the increased ball speed represented by a good smash factor is more important than increased clubhead speed. While a one-mile-per-hour increase in clubhead speed will get you a yard of extra distance, a one MPH increase in ball speed at impact produces nearly three additional yards.

Butler and Anderson agree that the trend to longer-shafted drivers for more clubhead speed is counterproductive, especially when the nine-out-of-ten that aren’t hit flush cost distance and accuracy.  A shorter driver hit on sweet spot more often, with a high smash factor, gets length and more often stays on the fairway.  Forget those nearly 46-inch long drivers, suggests Butler.  For men, 44 inches is plenty and for women 43.

Following are additional GEG questions and Doctor Grip answers:

GEG:  So you’re in a golf shop comparing drivers on a launch monitor, what do you look for?

Butler: If you can find a club that consistently gives you a launch angle of 14 to 15 degrees, a reverse ball spin rate of under 3000 revolutions per minute, and a descent angle of under 30 degrees, you’re close to having the right club.  That should give you the most carry and total distance for your natural swing speed.

GEG:  What about flex and kick points?

Butler:  Once you get those three numbers you already have the right flex and kick point, whether it’s high, medium or low.  And there, I’ve given away my secret formula.

GEG:  We’ve been through one of your fittings and know it’s more complicated, but do appreciate the help for off-the-shelf club-buyers.  What about irons?

Butler:  OK, take several six irons to work with and try to find one that gives you a launch angle of 20 degrees and reverse ball spin of about 5000 rpm’s.  That should give your shot a 45-degree angle of descent, which means the ball will land and roll out about ten yards.  You could go with a 14- degree launch angle and 3500 rpm’s, which gives a descent angle of 35 degrees.  That ball comes in low, hot and rolls out 25 yards or more.  But if you want score, it’s better to sacrifice distance with a predictable club that keeps the ball on the green.

GEG:  How about lie angle with off-the-shelf clubs?

Butler:  Many golf shops have a strike board and either tape or spray that shows where you’re getting the impact on the bottom of the club.  If it’s right in the middle of the bottom, you’re good.  You can also look at the clubface.  Figure a ball-sized circle at the center of the bottom half of the face is your sweet spot.  Many amateurs hit it about a half-inch out toward the toe.  Every one-eighth of an inch is a degree of lie angle.  So, if you’re a half-inch out on the toe, the club needs to be bent upright four degrees.  If you’re a half-inch toward the heel, it needs to go four degrees flatter.

GEG:  So you can get an off-the-shelf club’s lie angle adjusted?

Butler:  Well, yes if it’s forged.  Cast clubs break if you bend them too far. But at the least, take them to a club-fitter for the adjustment.

GEG:  And the TrackMan and its information?

Butler: Before I could afford the monitor I stood at the side of a golfer and watched his ball and judged the angle of its flight compared to marks on a board on the wall of the hitting area.  In retrospect I did a crappy job.  The numbers are incredibly useful when interpreted right.

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