Closure Rate

[Big Lex]

I have a few general questions about "closure rate" of the face of the club during the swing. The question grows out of data from a GEARS golf session I had a few days ago, and from a club fitting on a GC Quad launch monitor a few weeks ago. (I think this was the best forum area to post it, but the admins can move this obviously if they see fit.) 

1. What is the GEARS closure rate number, exactly? You end up with a fraction... .330 or .551 or whatever. What does this actually refer to? How many degrees (or radians or whatever) it rotates relative to some reference point? How fast it is rotating relative to a reference point? What is the reference point? 

2. What is considered a good closure rate in GEARS, and is it different for the different lofted clubs? 

3. Is closure rate something to "work on" per se, or is it a derivative data point that is related to other fundamentals of the swing that are more easily trained? 

4. The GEARS and various launch monitors' face-to-path number tells you how square your face is to the path the club is moving on. Let's assume your face to path is 0, and the swing is 3 degrees inside-out. Would GEARS have a closure rate of zero, or would it be some number derived from that 3 degree inside out path? 

5. Not related to GEARS per se, but in expert golf swings, is the face square to the path through a segment of the swing, or just at impact (on a straight shot)? How much opening and closing of the face relative to the path happens in expert golf swings? I know it's "not much," but I'm trying to get a sense of what that means. Do pros have the face lined up with the path when the club is 4 inches from the ball? Three feet? The entire downswing? 

Thanks. 

Edited May 20, 2022 by Big Lex
typo/clarification of one sentence

[billchao]

Gears Golf: Club and Ball Metrics - Gears Sports

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CLUB HEAD METRICS Club Path Angle of Attack Face to Path Spin Loft Closure Rate T Closure Rate Low Point Speed Impact Point Face Center Ratio to Grip Loft Face Center Address Impact Difference ... Lie Static Address...

The GEARS definition:

Quote

Closure Rate is a measure of the rotation of the club face as it approaches the impact point. This measurement is calculated relative to the club’s path.

Specifically, an angle is measured between the face of the club and the path of the club as shown. Closure Rate is the rate of change of this angle measurement (in degrees/second) of the club’s face relative to the club’s path.

We've discussed rate of closure in another topic, here:

A lot of things can affect rate of closure. There are tour players with high rates and low rates. It doesn't seem to correlate to accuracy. For amateurs, high rates of closure (in combination with other factors) could indicate other flaws in the swing, but there's probably better ways to measure and identify those flaws anyway.

Like spin rate on a launch monitor, I don't think closure rate is meant to be evaluated in isolation.

[Big Lex]

Thanks for the references! I looked on the GEARS site but missed that.....🙄

[iacas]

7 hours ago, Big Lex said:

1. What is the GEARS closure rate number, exactly? You end up with a fraction... .330 or .551 or whatever. What does this actually refer to? How many degrees (or radians or whatever) it rotates relative to some reference point? How fast it is rotating relative to a reference point? What is the reference point?

Bill answered this part, I think.

7 hours ago, Big Lex said:

2. What is considered a good closure rate in GEARS, and is it different for the different lofted clubs?

There's no such thing. Particularly if it's measured relative to time. If you swing at 1 MPH but your face closes from 6 to 8 the same amount as someone who swings at 200 MPH, your rate of closure as measured per second will be 200x higher, but if measured by the foot or some distance, would be the same.

Also, there are:

• Accurate players with high and low rates of closure.
• Inaccurate players with high and low rates of closure.
• Long hitters with high and low rates of closure.
• Short hitters with high and low rates of closure.*

* Though given the "per second" stuff longer hitters tend to be higher rates of closure just because of the stuff I noted above.

7 hours ago, Big Lex said:

3. Is closure rate something to "work on" per se, or is it a derivative data point that is related to other fundamentals of the swing that are more easily trained?

It's more of a "something that happens" thing.

7 hours ago, Big Lex said:

4. The GEARS and various launch monitors' face-to-path number tells you how square your face is to the path the club is moving on. Let's assume your face to path is 0, and the swing is 3 degrees inside-out. Would GEARS have a closure rate of zero, or would it be some number derived from that 3 degree inside out path?

No, because it's closing relative to that path.

7 hours ago, Big Lex said:

5. Not related to GEARS per se, but in expert golf swings, is the face square to the path through a segment of the swing

No. Never. Not even on most putts over a couple of feet.

7 hours ago, Big Lex said:

How much opening and closing of the face relative to the path happens in expert golf swings? I know it's "not much," but I'm trying to get a sense of what that means. Do pros have the face lined up with the path when the club is 4 inches from the ball? Three feet? The entire downswing?

You can see this in GEARS. Just look at the clubface pointer thing. I forget what it's called. You can show the clubhead vectors, too, and look at it from overhead or perpendicular to the plane at any point in time. The face won't be 90° to it for very long. An instant.

[Big Lex]

3 hours ago, iacas said:

10 hours ago, Big Lex said:

How much opening and closing of the face relative to the path happens in expert golf swings? I know it's "not much," but I'm trying to get a sense of what that means. Do pros have the face lined up with the path when the club is 4 inches from the ball? Three feet? The entire downswing?

You can see this in GEARS. Just look at the clubface pointer thing. I forget what it's called. You can show the clubhead vectors, too, and look at it from overhead or perpendicular to the plane at any point in time. The face won't be 90° to it for very long. An instant.

I have had one GEARS session, but I don't think those numbers and vectors are available to me in the information uploaded to my web locker. But I will look at it next time. 

Thanks very much for these replies, @billchao and @iacas. I think GEARS is extremely valuable because it gives by far the best and most precise data we've ever had on golf swings, and allows us for the first time to actually reliably quantify something like how square the face is to the path throughout the swing. This should put an end to alot of the pseudo-science that plagues golf instruction.

But to follow up on the question...if closure rate isn't a predictor of either distance or accuracy, does this mean it isn't necessary to try to work on the golfer's club face angle at point X or point Y in the swing? It just happens, and isn't a primary "error" or cause?

Other things I wonder about, and for which I doubt there are answers....Is there any parameter in GEARS which explains inconsistency in striking? Why one swing hits the ball flush and another swing hits it fat? Or in the toe? Is there any mechanical tendency which can be linked to inconsistency of path or face or impact point? Do these errors correlate with something else, like variation in the timing of a swing? I've always wondered why, among mid-low handicap golfers I play with (5-12 hcp), there doesn't seem to be much correlation in the correctness of the swing and how good someone is. Someone can have a rhythmic and elegant looking swing and be a 10, while someone else can have a more unconventional or ugly move and be a 6. 

Again...thanks. 

 

[Warlock]

21 hours ago, Big Lex said:

I have a few general questions about "closure rate" of the face of the club during the swing. The question grows out of data from a GEARS golf session I had a few days ago, and from a club fitting on a GC Quad launch monitor a few weeks ago. (I think this was the best forum area to post it, but the admins can move this obviously if they see fit.) 

1. What is the GEARS closure rate number, exactly? You end up with a fraction... .330 or .551 or whatever. What does this actually refer to? How many degrees (or radians or whatever) it rotates relative to some reference point? How fast it is rotating relative to a reference point? What is the reference point? 

2. What is considered a good closure rate in GEARS, and is it different for the different lofted clubs? 

3. Is closure rate something to "work on" per se, or is it a derivative data point that is related to other fundamentals of the swing that are more easily trained? 

4. The GEARS and various launch monitors' face-to-path number tells you how square your face is to the path the club is moving on. Let's assume your face to path is 0, and the swing is 3 degrees inside-out. Would GEARS have a closure rate of zero, or would it be some number derived from that 3 degree inside out path? 

5. Not related to GEARS per se, but in expert golf swings, is the face square to the path through a segment of the swing, or just at impact (on a straight shot)? How much opening and closing of the face relative to the path happens in expert golf swings? I know it's "not much," but I'm trying to get a sense of what that means. Do pros have the face lined up with the path when the club is 4 inches from the ball? Three feet? The entire downswing? 

Thanks. 

There is another thread about this where the discussion got a bit more detailed.

I sent an email to Michael Neff about the AMG videos where they showed 2 Pro golfers where 'Grip Roll' rate was increasing but 'Closure Rate' decreasing approaching impact (which didn't make sense to me at the time). He offered a telephone call to discuss but I'm going deaf so wasn't able to accept his offer.

I thought that maybe a change in the golfers club path was offsetting against the increased rotation of the clubface about the shaft axis (due to increasing Grip Roll approaching impact). 

I'm wondering whether Iacus figured out what 'Closure Rate' in rpm means (see below). I was also wondering what was meant by 'shaft rotational rate' as I thought that was the rotation of the shaft about its longitudinal axis (like Grip Roll).

 

On 2/15/2022 at 11:07 AM, iacas said:

Which… doesn't really seem to jive with the numbers I'm seeing from, for example, this multiple-time major winner:

GEARS tells me that at A6 and A7, the numbers are (rounded to integers):

• A6: 775°/sec grip roll, 512°/sec closure rate, 27.4 rpm closure rate^
• A7: 1745°/sec grip roll, 514°/sec closure rate, 431 rpm closure rate^

^ Why are these numbers different?

BTW, the path here was 1.86° out with a face 2.73° open. The frame here is just before impact.

The fact that 512° and 514° are similar, but 27.4 rpm and 431 rpm are wildly different, but both are listed as "closure rate" makes me wonder about a lot of things here. 😛

The thought just occurred to me that maybe the "rpm" one is the shaft rotational rate and the "°/s" is the clubface's rotational rate?