I was golfing one morning and noticed a greens keeper measuring the speed of the green.  She had a primitive looking device in which a ball rolled down it onto the green and she measured out the distance it rolled.  I had heard of the Stimpmeter and knew its basics – but to actually see one in use was like me pulling out the old slide-rule and figuring out the cosine angle of a triangle.  And hearing the “stimp” reading meant nothing to me.  To straighten it out, I have a detailed definition and history of the Stimp and Stimpmeter.

 The Stimpmeter is a device used to measure the speed of a golf course putting green by applying a known force to a golf ball and measuring the distance traveled in feet.  The device is an extruded aluminum bar, 36 in (91 cm) long and 1.75 in (4.45 cm) wide, with a 145° V-shaped groove extending along its entire length, supporting the ball at two points, half an inch apart.  It is tapered at one end by removing metal from its underside to reduce the bounce of the ball as it rolls onto the green. It has a notch at a right angle to the length of the bar 30 in (76 cm) from the lower tapered end where the ball is placed.  The notch may be a hole completely through the bar or just a depression in it.  The ball is pulled out of the notch by gravity when the device is slowly raised to an angle of about 20°, rolling onto the green at a repeatable velocity of 6.00 ft/s (1.83 m/s).

Stimpmeter Stimpmeter

The “Stimp” of the green is a measurement of how fast the greens are, as determined by use of a Stimpmeter.  The distance traveled by the ball in feet is the ‘speed’ of the putting green.  Six distances, three in each of two opposite directions, should be averaged on a flat section of the putting green.  The higher the Stimp; the faster the greens.  Stimp readings of 10 and higher are considered fast. 12 would be extremely fast – as fast as most professional tournaments are. 

History.  The Stimpmeter was designed by golfer Edward Stimpson, Sr. in 1935.  The Massachusetts state amateur champion, Stimpson was a spectator at that year’s U.S. Open at Oakmont.  After watching a putt by a top professional (Gene Sarazen) roll off a green, Stimpson was convinced the greens were unreasonably fast, but wondered how he could prove it.  He developed a device, now known as the Stimpmeter, which is an angled track that releases a ball at a known velocity so that the distance it rolls on a green’s surface can be measured.  Although the original device was made of wood, in 1976 it was redesigned from aluminum by Frank Thomas of the United States Golf Association (USGA).  It was first used by the USGA during the 1976 U.S. Open at Atlanta and made available to golf course superintendents in 1978.  The official USGA stimpmeter (painted green) is not sold to the public.

One problem on modern greens is finding a near level surface as required in the USGA handbook.  Many greens cannot be correctly measured as you cannot find an area where the measured distance or green speed in opposing directions is less than a foot, particularly when they are very fast requiring a very long level surface.  A. Douglas Brede was able to devise a formula to solve that problem. His formula:

stimp formula

(where S↑ is speed up the slope and S↓ is speed down the slope) eliminates the effect of the slope and provides a true green speed even on severely sloped greens.

For technical information, have a read of the following article.  The Green Speed Physics article by USGA Green Section Committee Member: http://turf.lib.msu.edu/1990s/1997/970312.pdf

(From various sources….)