Posts Tagged ‘attack angle’
There has been a fair amount of banter online recently regarding various topics and I thought it would help both of us if I jotted down a few thoughts:
A functional draw is one that finishes at the target – something many of us strive for. In order to hit functional draws you need a clubpath that is traveling outward (in to out) and a clubface that is angled slightly closed relative to the clubpath, yet open to the target (assuming center contact).
It is possible to hit both functional draws, ones that finish at the target, and bad draws, ones that move away from the target, with a clubface that is open, square and closed to the target at impact. You can even hit good and bad draws with the appropriate clubpath, but I believe an outward moving clubpath is integral to hitting functional draws. And here’s why…
I am yet to teach a golfer who fades the ball that consistently swings from in to out!
Clubpath is king and clubface is queen – I might get the desired shot shape with clubface, but I cannot get the desired result without clubpath. It is simply not possible to hit a functional draw with a clubpath that travels from out to in (assuming center contact). It is clearly not the only thing, but in my opinion it is the most important thing.
I am well aware there are many different ways to achieve this and whether as a coach or golfer you upgrade the clubface first or the clubpath first is entirely up to you. After all it’s all about results no?
Many golfers and TrackMan users are under the impression that smash factor indicates how well a ball was hit, or how centered the strike was – this is not necessarily the case. A high smash factor purely indicates high ball speed relative to club speed. Here is the simplified formula:
It is quite possible to have a smash factor with irons that is too high. Golfers who play from a closed face position and who tend to flight the ball low will often have a higher smash factor than golfers who flight the ball appropriately. This does not mean the low ball hitters are striking it better, it just means they are generating too much linear ball speed off of a particular club.
It is important for golfers to understand that ball type and condition, dynamic loft, clubhead mass, attack angle, CoR and of course quality of strike go into determining the smash factor for any given shot.
The objective with the driver should be 1.50 or higher, but with the shorter clubs a higher smash just might not necessarily better. Go for solid hits and ball flight over smash factor any day!
A Note to Golf Coaches:
I have made more than my fair share of mistakes in life. From these mistakes I have learned and improved as a coach and a person. One of the many valuable lessons I have learned from making mistakes is to never deride, belittle or insult another golf coach. It does nothing to enhance your image or reputation and you will never look better while attempting to make someone else look worse. Be wise when addressing other coaches and the methods they employ – you’ll be better off for it.
I was recently contacted by Swingbyte and asked to test their device to see how the data it generated held up against data generated by TrackMan. Please remember this is not a contest and I am not saying that TrackMan is perfect (I’m not sure there is such a thing), but I do believe TrackMan is the benchmark when it comes to reporting club and ball data in golf and I was interested to see how a $150 swing aid held up.
Swingbyte is a swing analyzing device that attaches to your club just below the grip and sends data to a mobile phone or tablet via Bluetooth. With a price point of $150 it provides a tremendous amount of data and sifting through the information on the App might be a little confusing at first, but with patience you will eventually find what you’re looking for.
Having used TrackMan for a long time one of the notable things I’ve found with passionate golfers is that the direction the clubhead is travelling through impact (attack angle and club path) is generally quite consistent. When testing/comparing other devices to TrackMan, whenever I see a dramatic change from one swing to the next in either attack angle or club path numbers a red flag goes up. With the Swingbyte I hit pitching wedges, 7 irons and drivers and I primarily keyed in on club speed, attack angle, club path and face angle. Here are my ratings out of a possible 5 stars:
If you purchased the device to simply know your club speed you are ahead of the game. It is important to enter detailed specs from each club into the App, but once you’ve got that done the feedback is surprisingly accurate. All the numbers I saw were within 4 mph of where TrackMan reported. (4.5 out of 5)
It is important to know that TrackMan and Swingbyte report attack angle from slightly different portions of the swing and thus differences should be expected, however I thought the device did a fairly accurate job most of the time. With the irons I felt the numbers indicated were close enough to “actual” in order to be actionable. It did seem that attack angles with the driver were a little too ascending. Their were also a few crazy numbers reported, but as you use the device more you’ll easily be able to recognize any outliers. (3.5 out of 5)
These numbers were a long way from what TrackMan was reporting and I would not put too much into this particular parameter. For example with the driver TrackMan reported my average club path on multiple shots was 0.2 degrees out to in, while Swingbyte indicated that every swing I made was from in to out with a range of 1.7 degrees to 13.6 degrees from in to out. (1 out of 5)
Even with TrackMan I seldom give much credence to the reported face angle as it is too easily influenced by off center hits and I most often use the reported number to determine where the ball was struck on the face. The original Swingbyte reports face angle at impact relative to where it was aligned at address. Assuming you have aligned the device on the club correctly, start with a square clubface and no twisting occurs, you might get an actionable reading – otherwise, I’d move on. (1 out of 5)
The problem Swingbyte has faced is that it could not latch onto a target – it only registered where the device was aligned at address. This means that any data regarding club path and face angle is based around where the device was aimed at address. The Swingbyte 2 addresses this issue. Founder and CEO, Alex Pedenko had the following to say:
You can now point your iPad and it will know what your target is and figure out all the numbers based on that. So now you have true, accurate numbers about what you did, not just in general but relative to the target line, relative to where you want it to go.
I am hoping that these upgrades will make this already useful device even better. While the device is not perfect (what is?) and should not replace quality coaching I feel that with a few practice sessions any golfer can start to gain a better understanding of what they need to do in order to make progress.
Few golfers are aware of what really happens when a clubhead collides with a golf ball at high speed, not to mention how much an off-center collision can effect the flight of the ball. My hope is that this article and the accompanying video footage will give each of you a much better understanding of the importance of solid contact.
I would encourage you to watch the following PGATour.com video a few times…
As you can see a strike away from the center of gravity of the clubhead will lead to twisting of the clubhead. While most of the twisting occurs after impact, a portion of it does occur during the impact interval. It is this twisting during impact that leads to gear effect which can greatly alter the flight of a shot.
An off-center collision will twist the clubface in any direction.
A hit high on the face will tilt the face upward and reduce the amount of spin on the ball, while a low strike point will deloft the face and increase spin rate. A strike towards the toe will open the clubface and increase draw or reduce fade and a strike towards the heel will close the face and increase fade or reduce draw. Interestingly, the clubface will tilt vertically (top/bottom) almost as much as it will horizontally (toe/heel).
There are seven shots in the video and if each of them had a neutral club face and club path during impact, the results of each shot due to gear effect would have been as follows:
Shot 1 – A strike above the “equator” of the clubface and slightly towards the toe. Ideal if you would like to hit high launching, low spinning, draws that go a long way.
Shot 2 – A more pronounced high, toe side strike. This strike point is too far from aligning with the center of gravity of the clubhead to be beneficial. This flight due to gear effect would have been fairly high launching, low spinning and would not have faded as much as it might have appeared.
Shot 3 – Another extreme high, toe side strike along with a heavy descending blow – not good. High and right, but a fairly straight flight.
Shot 4 – A severely off-center hit where the collision is with a very low portion of the face and in the heel. Believe it or not this ball gets airborne and will almost always be an unimpressive high spinning, low fade with very little distance.
Shot 5 – Charley Hoffman: I have seen numerous clips of high speed driver footage like this and I don’t think I have ever seen one where I cannot detect any twisting at all. A slight downward attack angle. Appears to be very close to a perfect center of gravity strike – a truly rare event! Very straight.
Shot 6 – Matt Kuchar: A neutral attack angle along with a high, toe side strike. High launch, lower spin and a slight draw – boom!
Shot 7 – Luke Donald: About as solid as Charley Hoffman’s shot, but the interesting thing about this clip is the attack angle – quite severely down. Solid and straight, but not optimal for maximum distance.
It is interesting to note that today’s larger clubheads will resist twisting due to having a higher moment of inertia. MOI is a measure of a body’s resistance to angular acceleration or twisting. MOI really comes into play when the ball and the clubface meet someplace other than the sweet spot. The MOI of a club is higher for heel/toe mishits than it is for high/low mishits and therefore tends to be more forgiving on heel/toe mishits. However, golfers tend to mishit a shot further towards the heel/toe than they do high/low so the clubheads’ resistance to twisting tends to even out.
Please know that physics is not selective and any golfer, pro or amateur, can hit any shot solidly or severely off-center. Also – no golfer can “stabilize” the clubface during or after impact due to an off-center strike.
This article shows you which part of the clubface is best.
I love this video footage and from here on out it will be required viewing for all my long term and golf school students. Would love to hear your thoughts….
There is so much complex information out there regarding the Ball Flight Laws – a ten second Google search yields enough confusion to get my head spinning for a month. The “old” or “new” ball flight laws, Dr. Wiren, TrackMan…..who or what should you believe?
In light of Dr. Einstein‘s insightful quote I am going to give this touchy topic my best shot and try to keep it as simple as possible. Please don’t check out! This is important information for any golfer to comprehend, so bear with me and you’ll gain a far better understanding of why your golf ball reacts the way it does.
There are only four factors that influence ball flight when clean (not necessarily solid) contact is made between a golfball and a clubface.
The faster the clubhead travels the further and higher the ball will travel – generally with more spin. Compare a chip (slow speed) with a pitching wedge vs. a full swing (faster speed) with a pitching wedge…simple enough.
Orientation is a fancy term that refers to where the clubface is angled. Keep in mind that the face angles both left or right or up or down – left or right being an open or closed face and the up/down variable (although hopefully never down) referring to the loft imparted at impact (dynamic loft). The face angle largely determines where the ball launches – left or right of the target and at what angle relative to the ground. A good general point to remember is clubface (for the most part) = launch.
Once again the direction the clubhead travels relative to the target line at impact – left or right (clubpath) and up or down (attack angle) – plays a role in determining ball flight. A lesser role than the clubface, but a role nonetheless. A good general point to remember is clubpath (for the most part) = curve.
Centerdness of Contact
This is a big one and something the vast majority of teachers and golfers tend to underestimate. Most golfers strike the ball on the sweet spot far less frequently than they think . I often see golfers that swing for a draw, yet strike for a fade – in other words they have a clubpath that is in to out, yet hit the ball slightly out the heel which leads to a fade. An off center point of contact on the face leads to gear effect, which overrides or reduces the effect the face orientation and clubhead direction have on ball flight. This factor plays a bigger role than most realize – watch out for it. And the best way to do that – a spray of Dr. Scholl’s foot powder.
Here are a few simple factors to understand and remember:
- The ball launches primarily in the direction of the face – varying degrees of up and either left or right.
- Given a centered hit, clubpath leads to curve. With the curve being away from the clubpath.
- Hitting down does not increase spin, and conversely, hitting up does not necessarily reduce spin.
- Heel hits encourage fades or reduce hooks and toe hits encourage draws or reduce slices.
- The more you hit down on the ball, the more you will swing in to out and the more you hit up on the ball the more you will swing out to in.
Now that you’re finished reading shoot back up to the top and read again. This is vital information to assist with your understanding of of how your golf club “communicates” to your golf ball.
If you’d like to try out your new understanding of the Ball Flight Laws in southwest Florida check out this Fort Myers Golf Guide for a great course to play.
Thanks for reading and feel free to fire away with any questions you may have…..
My good friends Tim and Simon Cooke from GolfPrep on Hilton Head Island recently brought their new Flightscope X2 out to Berkeley Hall. Our objective was to learn more about the numbers that TrackMan and Flightscope are putting out and we wanted to get a sense of how well one machine performed relative to the other.
I have pondered the best way in which to convey my findings and have finally committed to just simply jotting down my thoughts. My intent is certainly not to create controversy or confrontation – these are simply my own honest impressions from the day. Please also keep in mind that I am a TrackMan owner and supporter and no matter how I attempt to remove my bias I doubt whether I am able to remove all of it…
- Prior to the test I had been having trouble with my TM unit giving unusual spin numbers every 30-40 shots, something it had never done before. As a result I had contacted TM support and was informed that I more than likely had a bad USB cable. I was also informed that the classic indicator of a bad cable would be a “double” or “half” spin. Sure enough during the test TM gave out three spin numbers from the 60 shots we hit that were right around double what the FS reported. I have since replaced the cable and have yet to see a spin rate that seems odd.
- As you peruse the following thoughts keep in mind that good players , which all three of the test subjects were, are very good at controlling the direction the clubhead travels (angle of attack and club path) from shot to shot. The direction may not be ideal, but better players are consistent with clubhead direction. That means that dramatic changes in either of those categories, along with sizable changes from shot to shot in club speed, were going to draw my attention and raise a red flag.
- Since running the tests I have spoken to many “in the biz” people about radar interference. It was mentioned that the machines, when set up side by side as we had them, will occasionally give corrupted data due to the influence of the outside radar. I have not run enough tests to ascertain if this is or is not the case, but during the testing the FS seemed to give a few numbers that were incorrect and this could be due to the TM being directly alongside the unit. The TM did not do anything different to what it normally does as it seemed to be unaffected by the additional radar.
- If a shot off turf has a decent size divot TM will only provide ball data and no club data, whereas FS reported both ball and club data for just about every shot hit off the ground. On the occasions that FS reported club data and TM did not the numbers did not look correct – meaning the attack angle and/or club path seemed to be too far from what the subject would normally generate. We hit numerous 50 yard pitch shots and TM did not offer any club data while FS reported for most of these shots. The problem was that the club path was said to be almost 15 degrees from in to out along with a spin rate of 14,000 rpm – just not happening! I actually preferred that TM did not provide club data as I would rather have no information than have to explain away improper information. That being said I would love a radar that provided correct club data on all shots.
- With both units unplugged and PC’s powered down the TM (2:05) was aligned and ready to roll in about half the time of the FS (4:16). I was told that with an iPad the FS can be aligned and operational in far less time.
- We noticed that both machines reported different Swing Plane numbers when they were moved (flipped positions) relative to the same golfer. I have tested this before and the changes in data are due to the hardware in the TM II. Each machine appeared to provide better data when the golfer is hitting shots aligned with the center of the unit – something that was not possible when running two machines.
- We tested the ability of each unit to report gear effect, by logging the point of contact on certain drives and then comparing each units Face to Path and Spin Axis numbers. The TM reported gear effect as I would have anticipated and most of the time FS reported along similar lines. However the first shot we examined, a big heel hit, was actually reported by FS as being a slight toe side hit. TM reported a Face to Path of -9.3 and a Spin Axis of -5.4 while FS reported a Face to Path of -2.2 and a Spin Axis of -11.0
- I was amazed at how closely aligned the Spin Rate numbers were for each machine. Unless there were dramatic differences the spin rates were almost always within 100 rpm’s.
- There seemed to be quite a few instances during the testing where the attack angles were not even in the same ball park. I had nothing to help me determine which machine was correct, other than the aforementioned fact that better players tend to be very consistent, and all too often it was FS reporting wide ranges of variation from the player.
Keep in mind that my intent is merely to report what I observed and not to offend anybody or any entity. I could tell that Tim and Simon were a little concerned with the results and they went home and performed additional tests. I am happy to report that the FS performed much better without the influence of additional radar and when shots are hit from the center of the unit. Tim’s follow up comment to me was:
I believe that side by side testing, although seeming to be a good idea, does not work. Clearly there was some radar interference at work as the inconsistent numbers were not reproduced in stand alone tests. Maybe the only way you can really compare the units is with extreme high speed cameras with the units working independently of one another.
I would have to agree with Tim’s sentiments and I have started to make plans to have each unit test the same golfer on the same day, but without the potential interference of outside radar.
You know I’ll report back on that one….