Ask the expert: Dick Rugge
Dick Rugge, senior technical director, U.S. Golf Association
Golfweek spoke with Rugge about upcoming rules changes that will limit the dimensions of grooves in many clubfaces. Professionals must switch to the reduced grooves in 2010, but most non-elite amateurs will be able to play clubs with the larger grooves until at least 2024.
Golfweek: Why change the rules?
Dick Rugge: Many players are able to produce too much spin from the rough. The larger cross-sectional area (found on most grooves today) channels more of the water away. It doesn’t have to be wet grass, just grass – it’s full of moisture. The grooves act like treads on tires.
GW: But the rule change will decrease spin on shots around the green, correct?
DR: For the best golfers, yes, to some degree, although the biggest change they will see will be on shots from the rough. With Surlyn-covered balls, there will be no difference whatsoever, and two-thirds of the balls sold (in the world) are Surlyn.
GW: Do the new rules prohibit U grooves?
DR: No, absolutely not. Clubs have to have a (smaller) cross-sectional area (total area of all grooves). So a club might have a combination of U grooves and V grooves, or it might have U grooves that are shallower, less broad or farther apart. (For the record, V grooves occupy about half the cross-sectional area of U grooves.)
GW: The edges of the new grooves will be different?
DR: Yes. The rule book for years has said that grooves must not be sharp by a finger test. We have defined that to a certain minimum-edge radius – approximately ten-thousandths of an inch minimum radius, which is a relatively dull edge. They are pre-dulled, if you will.
– James Achenbach