Putter Face Design: Textures and Grooves
Posted by: mike May 31st, 2017
By John Ambrose, President and Design Innovator at L2 Putters
In an effort to find yet another way to promote putter sales, golf club manufacturers occasionally try to wow their customers with tales of amazing face inserts that have the ability to create instant ball roll for better direction and distance accuracy. They make what sounds like a variety of grooves and textures that they claim will get the ball to roll instantly without skidding or hopping. Considering the limitations the USGA has in place concerning this club design feature, they sure sound like they have another "new idea" designed more for sales than for performance..
The information below was taken from the USGA rules on face insert designs for putters:
.... any grooves or other permissible markings on a putter face must not have sharp edges or raised lips.
Additionally, if a groove or the grooves on the face of a putter exceed 0.035 inches in width and 0.020 inches in depth, the following guidelines apply:
The width may not exceed 0.06 inches.
The width to spacing ratio must be no less than 1:1.
The depth must be less than the width, and may not exceed 0.04 inches.
In short, this means that the grooves on a putter face are not big enough, sharp enough, or deep enough to impart any major influence on ball roll. The amount of impact energy needed for putting does not produce enough force to create the kind of friction between the dimples on the ball and the face to produce this over-spin effect. Limiting the effects of a putter’s face texture or grooves at ball contact is the exact intent of these rules. If an increase in stroke energy should be needed for a long putt, the loft of the face at contact will take over the influence of the ball before the grooves will.
Now if you want to discuss over-spin, hopping or skidding a ball at contact, the loft of the putter and the force used to get it a particular distance is a different matter.
Making contact with the ball at its equator will transfer the truest amount of intended energy to it with the least amount of influence on the ball. However, on a short putt, (5' and in) contacting the ball slightly below its equator could evoke an over-spin which does hold the track line better. However, because of the way the ball slightly sits into the green, combined with its relatively light weight, this over-spin should not be counted on as the distance of the putt increases or on slower greens. A slight hop at impact is not uncommon to see on most putts since the ideal spot along the swing arc for ball contact is just in front of its lowest point which means on a slight up stroke. However, this upstroke at contact can go too far producing a high hop and bounce. This is usually because the putter is being propelled more by your dominant hand which will cause the arc to go up instead of through the ball. Not only does this disrupt direction control, but by making such an upward force on the ball, you will have lost some of the intended forward energy causing the putt to come up short. Remember that a putter face not only has a horizontal sweet spot that is not very large,( about one dime wide) but it also has a vertical sweet spot which is actually smaller and less forgiving. A smooth stroke through the ball rather than a hit at the ball, will go a long way to insuring solid vertical sweet spot contact.
The opposite of too much loft would be negative loft which would produce a skidding motion as you drive the ball slightly into the ground as it begins its movement. This type of contact can lead to more direction and distance control issues then hopping does, but either extreme is not desirable. Your putting mechanics, along with the small light putter you are using, is usually more to blame for a poor putt than a lack of forward ball rotation.
So if you want to get the truest response from the ball in both distance and direction, pay more attention to the face loft and direction at impact and don't buy into yet another sales line designed to simply sell you a putter that will promise you the moon but will be destined to end up in your garage with the rest of the collection.
John is a retired commercial airline pilot of more than 25 years for United Airlines (formerly Continental), who has applied the physics of his profession to the performance qualities of the L2 design. John is also a certified USGTF (United States Golf Teachers Federation) instructor, a former First Tee coach, Director of instruction at Hemlock Springs G.C., and a certified Vector Green reading instructor.