Andrew Rice Golf

Posts Tagged ‘short game’

Let the Wet Test begin...

I recently stumbled onto an interesting tidbit whilst working with a young professional on his wedge game. It was early in the morning and we had been hitting beautiful 50 yard pitches the afternoon before and suddenly he could not get the ball to launch low enough with the spin rate he had been generating the day before. Now as you may know I’ve tested almost all there is to test in regards to a 50 yard wedge shot and of course I had looked into the effect of water interfering with the friction between the face and the ball. One problem – I had tested a wet club striking a dry ball. My results from the earlier test showed very little difference in launch and spin when there was water involved and I had since adopted that belief.

As I watched the young pro struggle to lower his launch in the morning dew it came to me – there was a difference between a wet club striking a dry ball and a dry club striking a wet ball! I had to run the test again.

Titleist NXT Tour

I had to be very careful with the test in that I needed to use the same club, my 54 degree sand wedge, in very controlled conditions, with golf balls that were consistent. I used brand new Titleist NXT Tour golf balls and made sure that I cleaned the grooves and clubface off between each shot. I attempted to hit each shot to carry 50 yards flat and hit eight shots for each portion of the test. I removed the two shots that had the lowest spin from each portion. With the help of my TrackMan here are the results:

Wet club and dry ball:

• Launch angle was 27.8 degrees
• Spin rate was 5463 rpm
• Height was 26.5 feet

Dry club and wet ball:

• Launch angle was 30.1 degrees
• Spin rate was 5291 rpm
• Height was 28.4 feet

Dry club and dry ball:

• Launch angle was 25.4 degrees
• Spin rate was 6603 rpm
• Height was 21.2 feet

Trajectory Chart from the Wet Test

The interesting thing in looking at the trajectory chart is how much lower the dry club and dry ball (purple) shots flew. Clearly there was more friction between the face and ball which led to a lower launch with substantially more spin. The dry club and wet ball (yellow) sample flew the highest as the water on the ball greatly decreased friction which led to higher launch, due to slippage and thus decreased spin – certainly not the optimal shot.

The interesting thing when comparing the wet club/dry ball versus the dry club/wet ball results was that the spin and launch were better when the BALL was dry. This was due to the water being forced off the clubhead and into the groove channels during the motion of the swing. Not to mention that the air dried the face during the swing too.

Moral of the story – always clean the clubface (unless it has sand on it) and dry the club and ball when possible. If you happen to have an early morning tee time and you’re a dew sweeper, don’t plan on hitting any low spinners! The drier the ball and club, the better the friction and the better the quality of shots you will hit.

Please read my first two articles on wedges and pitching:

The Science Behind Superb Wedges: Part I | Andrew Rice Golf

The Science Behind Superb Wedges: Part II | Andrew Rice Golf

So Many Choices...

In my quest to better understand pitching, chipping, and more specifically the low spinning wedge shot I needed to watch different professional players hit a variety of shots and be able to track the data from each shot.  My objective was to understand how friction or grip between the face and the ball influenced the launch angle, height and spin rate.  I have named the measurement of this grip and it’s influence on the golf ball – friction launch.

I need to explain some fairly detailed physics as to how I measure friction launch, so bear with me.  The golf ball always launches somewhere between where the face is angled and where the clubhead is travelling – on both a vertical and horizontal plane.  The ball also always launches closer to where the face is angled than where the clubhead is travelling.  Where the ball launches between the face angle and the clubpath is primarily determined by club speed and friction between the face and ball.  I needed to measure this friction in order to see how it effected the trajectory and spin on wedge shots.

With the help of Mark Reilly and Edoardo Molinari, we came up with the following formula to determine friction launch:

(Dynamic Loft – Launch Angle) x 100/Spin Loft = Friction Launch

This formula informs us where the ball launches between the face and path. The percentage indicates how far below the face angle the ball launched. A friction launch of 0% indicates that there was absolutely no grip at impact and the ball launched in the direction the face was angled at impact.  A friction launch of 50% would indicate that the ball launched directly between the face angle and the clubpath and the grip was exceedingly high.  By the way – neither of these are possible under normal conditions. The smaller the percentage, the higher the launch and lower the spin and vice versa.

With all the various situations I tested I needed to keep certain factors constant in order to be able to detect why the trajectory and spin rate of each shot was altered.  My constants were TrackMan – to record the data; the golf club – a Titleist Vokey SM4 54 degree wedge; and the distance of each shot studied – 50 yards.  If any ball landed short of 40 yards or longer than 60 yards it’s data was thrown out.  The factors I controlled were the quality of the lie and playing surface, the grass and dirt in the grooves and on the face and the type of golf ball.

The Test Subject

Here are the average results attained from three professional golfers hitting 10 shots each in 7 different situations:

1. Clubface packed with dirt and grass/ProV1/off lie board (to eliminate additional matter)

• Friction Launch 17.9 degrees/Spin Rate 4408/Launch Angle 34.9 degrees/Height 31.9ft/Carry 51.6yds

2. Clean clubface/ProV1/off lie board (to eliminate additional matter)

• Friction Launch 28.1 degrees/Spin Rate 6501/Launch Angle 28.4 degrees/Height 25.1ft/Carry 50.3yds

3. Wet clubface/ProV1/off lie board (to eliminate additional matter)

• Friction Launch 28.1 degrees/Spin Rate 6564/Launch Angle 28.7 degrees/Height 25.7ft/Carry 50.4yds

4. Clean clubface/ProV1/off turf/preferred lie

• Friction Launch 31.9 degrees/Spin Rate 7178/Launch Angle 26.1 degrees/Height 22.3ft/Carry 48.9yds

5. Clean clubface/hard range ball/off turf/preferred lie

• Friction Launch 28.8 degrees/Spin Rate 6625/Launch Angle 27.6 degrees/Height 25.1ft/Carry 50.8yds

6. Clean clubface/ProV1/off a new mat

• Friction Launch 30.4 degrees/Spin Rate 6859/Launch Angle 26.8 degrees/Height 23.3ft/Carry 49.2yds

7. Clean clubface/ProV1/Off a tee

• Friction Launch 30.6 degrees/Spin Rate 7259/Launch Angle 27.6 degrees/Height 24.8ft/Carry 51.2yds

Edoardo Molinari was also kind enough to submit his TrackMan data to me from the 10 shots he hit with his 60 degree wedge and 10 more with his 56 degree wedge: (the following shots were hit with premium golfballs, off preferred lies and cleaning the clubface between each shot)

60 Degree Wedge

• Friction Launch 22.9 degrees/Spin Rate 6048/Launch Angle 36.2 degrees/Height 34.8ft/Carry 51.0yds

56 Degree Wedge

• Friction Launch 24.4 degrees/Spin Rate 6046/Launch Angle 34.2 degrees/Height 31.5ft/Carry 50.5yds

NOTE: After a few weeks of practice Edoardo has improved his 10 shot average with his 60 degree to a spin rate of 8700rpm and a Launch angle of 26.1 degrees! There is something to this…

The deductions I took from the above tests are as follows:

• Shots out of the rough, first cut or even into the grain lies are always going to launch higher, spin less and as a result fall out the sky faster and roll more after landing – no matter how good you or your wedge is.  There simply is too much ‘matter’ involved between face and ball to create optimal friction.
• A wet clubface actually makes very little difference in determining how much friction, and thus spin, is imparted on the ball.
• A premium golfball makes a noticeable difference with the wedges.  Not only will it add distance off the tee, but it will also allow you to hit better and more predictable short shots.
• If the rules allow you to tee the ball up – go ahead and do so.  You increase your ability to place the clubface cleanly on the back of the golf ball.
• Hitting pitch shots off mats is a fantasy world and can only increase the ‘illusion of competence’.  No bad lies, nothing between the face and the ball, minimal consequence to heavy shots...
• For pitch shots, higher lofted clubs do not spin the ball significantly more than the next wedge down (60*vs56*). They do, however, get the ball to stop slightly faster due to a steeper landing angle.
• Average friction launch for a 50 yard shot is around 25%.  The lowest friction launch was out of the poorest lie (18%) and the best results came from an ideal fairway lie, a new and clean wedge along with a premium golfball (32%).
• The quality of the lie is the most important factor in allowing a golfer to control the trajectory and spin of the wedge shot they are about to play.

Let’s take a look at the factors that influence friction launch:

The Golf Club

• The sharpness of the top edge of the groove will effect spin, yet most of the spin on a shot comes from the roughness of the area between the grooves.

• In my opinion the wedges that provide the highest amount of spin are the models that have the roughest surface between the grooves – the new TaylorMade ATV and the Nike Vr Pro wedges seem to do an excellent job with ‘between groove’ treatment.
• An excellent way to improve spin with your current wedges is to have the face sandblasted with normal aluminum oxide sand.   This will provide a rougher, more ‘grippy’ texture to the face.
• The number of groove edges that come into contact with the ball also effects backspin.  In pushing the limit of the groove rules manufacturers can now put five grooves on the surface of the ball at impact versus the traditional three.
• Grooves channel away some of the moisture and matter from rough that gets between the ball and face – but seldom all of it.
• The grooves and face of your wedges should always be very clean – even when you’re practicing.  Keep a towel or brush handy to clean the club after every few shots.
• If you are serious about competitive golf I would recommend having a tournament set of wedges and a set you use in practice. Every shot you hit wears down the face which reduces friction at impact.
• In fact Gary Player would ensure that his caddie never cleaned his wedge after hitting a sand shot – the sand particles on the face helped to create more friction between the face and ball for his next shot.

Turf Type and the Quality of the Lie:

• When you are into the grain you will often get grass caught between the ball and the face, thus reducing grip.  A down grain shot will ‘cut’ very little grass and thus allow for clean contact and increased grip.
• Different turf types are thicker and stronger and thus, even at fairway height, support the ball enough to keep it up and away from the grass.  This makes it easier to have a higher friction launch factor.  If you’ve ever played off kikuyu grass you’ll know what I mean.
• When laying up on a par five understand the value of high friction launch – lay up in the fairway and don’t be greedy.

The Swing

• This is where I am now focusing my efforts.  There does seem to be a method that DOES NOT involve a more open face, increased speed, higher launch or a cutting action that seems to produce a lower trajectory with a much higher spin rate. Stay tuned…..

Read part one of this article HERE

When it comes to the shortgame it is vital that the golfer strikes the ball and the ground on every shot – and preferably in that order! Golfers run into trouble when the club contacts the ground before the ball, particularly with a closing clubface as the leading edge will dig into the turf. There is no quicker way to deplete confidence than to start  alternating between bladed and heavy pitch shots.

A helpful drill is to practice hitting 40-60 yard pitch shots with an 8-iron. Try to get the ball up in the air, with a slight cut action and have it land softly. This will give you the sense of keeping the face open and using the bounce of the club correctly. It will also prevent the wrists from being overly active. A feeling to key in on is the sense of swinging to the inside after impact (as pictured below). Be sure to keep the face open or looking up while the club tracks to the inside as this will prevent the leading edge from digging.  This is rapidly becoming one of my favorite drills!

Think of the bounce on a wedge, or any iron, as an insurance policy against digging the leading edge of the golf club into the ground. 

It is very important for any golfer to not only understand what the bounce is, but how to use it to their advantage.  An excellent exercise to do every now and then is to hit a few pitch shots off of a lie board. This is a flat plexiglass board that most club fitters use in determining the correct lie angle a golfers irons should be set at.  If you do not have access to a lie board, use a piece of plywood painted black. Just be sure to not hit any shots where the ball is too close to the edge of the board.

What you should see...

If the markings on the sole of the club are as pictured above you are using the club correctly.  Should they be closer to the leading edge you might be in danger of sticking the club into the ground on your next chip of pitch.  The most important aspect of using the bounce correctly is addressing the ball correctly. Take a look:

The Set Up for a Chip or Pitch

In the above image you will see the ball positioned in the center (watch out for too far back as it reduces the bounce at impact and makes it easier to do some gardening); the feet are fairly close together; and the hands and weight are just slightly in front of the ball, with emphasis on slightly.

As you go through the motion of striking that chip or pitch try to feel that the handle and the clubhead get back to impact at the same time – in other words don’t allow the handle to get too far in front of the clubhead at impact as you are then exposing more of that sharp leading edge to the ground.  And we all know what that can lead to…..

The Bounce Angle

Golf club bounce is the angle between the ground and the sole of the club when the shaft is held in a vertical position.

 

 For example: A club with ten degrees bounce will have a ten degree angle between the sole and the ground (barring any rounding of the sole).  Notice how the back edge of the sole of the wedge rests on my finger, while the leading edge is slightly raised. Thanks to Gene Sarazen, who first invented bounce, irons have been built this way to deter the leading edge from shoveling or digging into the ground.

 The greater the bounce angle of a club, the higher the leading edge will be from the turf at address and vice versa. It is important to note that all modern irons have bounce built into them; it is not something that is strictly reserved for the wedges.

A stock set-up for chipping

There are two things that must be struck with every chip or pitch: the ball and the ground. And preferably in that order! This is where understanding and using club bounce comes in. Most golfers know that a chip or pitch must be struck with a descending blow. The dilemma that most golfers face is how to hit down without getting the sharp leading edge of the club stuck in the ground. For the majority of short game shots, the handle should beat the club head to the ball, similar to the full swing, but to a far lesser degree. If the handle gets too far forward, the bounce is removed and the club will dig too much. I find that golfers struggling with their short game are often alternating between sticking the club in the ground and blading shots over the green. This is where using the bounce correctly becomes vital: Think of it as an insurance policy that, when used correctly, allows for an acceptable result even with the ground being struck before the ball.

Bounce Drill:

Locate a lie board (a flat, sturdy plexiglass board) and pitch a few shots from the board. You will notice that the back edge of the sole of your wedge is marked up from where it made contact with the plexiglass. Should the markings be too close to the leading edge, your hands are too far forward at impact and you are preparing to do some gardening.

Using a lie board

If you do not have access to a lie board, (try plywood with paint on it) you can just make a few small practice swings during which you attempt to brush the ground with the back edge of the bottom of the club. There should be no divots – no matter what the turf conditions.

• The leading edge digs into the ground; the bounce glides along the ground. Use the bounce!
• If your club has ten degrees of bounce and the shaft leans forward more than ten degrees at impact, you effectively have zero — or even a negative — bounce.

Negative Bounce

• There should be no divot when you hit a chip shot. If the leading edge is cutting turf, you are not employing the bounce correctly. Divots with pitching will depend on turf conditions, but there should not be any digging there either.
• Lagging the clubhead into impact will lead to a loss of bounce and inconsistent results. Feel as if the hands and clubhead arrive at the ball at the same time. 
• The ground must be contacted for there to be an acceptable result. Preferably after impact.

Thanks for reading and please feel free to let me know your thoughts!