Welcome to MythBusters, a Golf Digest series where we explore answers to some of golf’s most common questions through a series of tests with real golfers. While our findings might fall short of definitive, they still aim to shed new light on topics that have consumed golfers for years.

Walk down any PGA Tour driving range and you’ll see players using towels, brushes and tees to clean their grooves after every shot. As the clubs get shorter, players seemingly get more obsessed with making sure their clubfaces are free of any dirt. More than just a mindless task, there is a belief that a dirty clubface reduces spin and creates inconsistent distance control.

Throughout the bag, spin plays a crucial role. With a driver, for example, if you have too much spin, you’ll sacrifice distance, and too little spin will cause the ball to tumble quickly out of the air. That give-and-take with spin continues with irons. We’ve all hit that knuckleball 7-iron that scurries through the green. Not enough spin. Or that ballooning shot that gets eaten by the wind. Too much spin.

With shorter irons and wedges, most golfers rely on spin to create a more consistent trajectory and faster stopping power. It’s the difference between an approach that tumbles over the back and one that takes one hop and stops. On pitch shots, more spin often increases a golfer’s margin for error, as he or she doesn’t need to rely solely on height to stop the ball near the hole.

In other words, we know spin matters, but when it comes to maximizing spin, does a clean clubface matter as well?

Our test

To measure whether a dirty clubface affects spin and distance control, a Golf Digest staffer and +2 handicap, Drew Powell, hit five 100-yard shots with a 60-degree wedge with a clean clubface, and then five with a dirty clubface. The dirty clubface was created by taking a divot and not cleaning the grooves, simulating the reality for any golfer who doesn’t clean his or her clubs. We measured spin rate using Foresight Sports’ GCQuad launch monitor in the ninth fairway at Tamarack Country Club in Greenwich, Connecticut.

What we found Clean clubface

Shot 1: 11’10”, 8,314 rpm (revolutions per minute) Shot 2: 49’, 11,164 rpm Shot 3: 6’ 2”, 10,065 rpm Shot 4: 7’ 9”, 12,230 rpm Shot 5: 22’ 3”, 10,989 rpm

Avg. proximity: 19’ 5”Avg. spin rate: 10,552 rpms

Dirty clubface

Shot 1: 18’ 1”, 7,574 rpmsShot 2: 7’ 2”, 5,814 rpmsShot 3: 45’, 5,748 rpmsShot 4: 6’ 11”, 3,949 rpmsShot 5: 14’ 10”, 5,679 rpms

Avg. proximity: 18’ 5”Avg. spin rate: 5,759 rpms

What does it mean

We found that a dirty clubface has a substantial effect on spin rate. The average spin rate with the clean clubface was just over 10,500 rpms, which is nearly double the average of 5,759 rpms with the dirty face. For reference, the PGA Tour average spin rate for a full lob wedge is roughly between 10,000 and 11,500 rpms.

This radical change in spin rate is due to how dirt affects the grooves on a club. When the clubface is entirely clean, the grooves play to their full depth and have the maximum ability to grip the ball, which creates spin. When those grooves are filled with dirt, however, they are effectively much shallower, which decreases friction and spin.

In practice, this disparity in spin had a tremendous impact in how the ball reacted on the green during our test. With a full swing from 100 yards with a lob wedge, the balls struck with a clean clubface landed about hole-high, took one bounce forward and spun back significantly on the fairly soft greens.

The average proximity on these shots was about 19 feet, with three of the five shots ending up inside 12 feet. Two shots, however, landed short of the hole, so after spinning back, they ended much farther from the hole.

With a dirty clubface, on the other hand, the balls didn’t spin back nearly as much. Interestingly, these shots landed about the same distance as the clean clubface shots, but the ones hit with dirty grooves mostly took one hop and stopped, resulting in a proximity that was actually one foot closer.

A couple factors are worth considering. With Powell being a scratch golfer, taking a full swing with a lob wedge and hitting into a soft green, maximum spin wasn’t ideal. The vast majority of golfers in most instances, however, would benefit from maximizing the spin they produce with their wedges, which can be done by cleaning the clubface.

Verdict

A clean clubface significantly increases spin rate versus a dirty clubface. Clean grooves produced nearly double the amount of spin as dirty grooves on a full shot with a lob wedge.

While we tested full shots, this disparity in spin rate is significant on chips and pitch shots, as well. When you fail to generate enough spin on short shots around the greens, your margin for error decreases—you must land the ball in the perfect spot for it to roll out to the hole. And you need plenty of green to work with to plan for this roll out.

With more spin, however, you can land the ball closer to the hole and get it to check up faster. This is particularly important on short-sided shots, where quick stopping power is essential to keep the ball close to the hole.

And as our test demonstrates, one crucial factor to maximizing the amount of spin and control you generate is making sure your clubface is fully clean before hitting a shot.

false Private Tamarack Country Club Greenwich, CT, United States 4.3 78 Panelists

Situated within a mecca of great golf courses, Tamarack Country Club stands out as one of the finest. Built by Charles Banks in 1929, the course includes many template holes that were the trademark of Banks’ mentors, Seth Raynor and C.B Macdonald, and a few great original holes on the back nine. The course is memorable for its massive scale throughout the property, often allowing players to recover from wayward misses. Though Tamarack delivers options in where you can hit it, the brawny course makes it difficult to score if you’re not in the correct spots. View Course

This article was originally published on golfdigest.com