Driver Smash Factor

[Killa]

So we are training a lot indoors over this winter and alongside is one of our hopeful touring pros, so we are talking about a +5hcp at a minimum. 
 

He has to play Ping clubs so changing the driver is out of question, he was fitted in an aftermarket shaft. 
 

Now while he is hitting indoors (can’t hit outdoors anywhere atm) his driver smash factor never goes above 1.46 and even that is very rare. This is all measured with a TM4 and a dot on the ball. When I go hit my driver I can reach 1.48 but my highest outdoor was 1.51. His swing speeds are around 120 mine around 110 when I’m hitting my on course swings. 
 

Now we all find it very curious that a player of that caliber couldn’t hit at least 1 ball in the 1.5 range when he is hitting 100 balls. So what would be the parameter to look for as to why he can’t get the smash up? Because his swing speed is around 120 and his ball speed was 173 at the highest today usually around the 170 range. 

[Adam C]

Don't worry about SF. Trackman is trying to measure ball data and club head data at the same time.  It can have difficulty measuring the club speed because of how and where it tries to measure from depending on the driver head design. The radar always has some issues with it. That often leads to inaccurate club head speeds and therefore inaccurate smash factor numbers.

Just focus on ball speeds, that is what matters.

[TourSpoon]

1 hour ago, Adam C said:

Just focus on ball speeds, that is what matters.

Good tip! I have noticed some discrepancies from different units indoors and out, but this data point has been stable. 

[iacas]

I disagree with that. Trackman and FlightScope are really good about understanding and measuring clubhead and ball speeds. They're great tools for tracking the speed of things, as radar is, and SF is just the division of one number by another, so SF is generally considered very accurate too.

Smash factor is a good way of knowing whether you're achieving a few things:

• Consistency of contact.
• The "proper" amount of shaft lean/AoA/"compression"/etc. on the golf ball (you can over-do it and get low launching balls with less spin and too high a SF).

If you know exactly where you're hitting the ball on the face, that should track pretty well with the smash factor assuming somewhat consistent impact conditions (as a +5 would have).

Now, it's important to know WHEN and WHERE and HOW the various radars measure clubhead speed. For example, is the center of the mass or "blob" of the clubhead measured? If so, the "clubhead speed" will be a bit lower than what the toe of the club is moving, and you can thus get some smash factors above the theoretical 1.5 if you catch the ball on the toe a little. Also, FlightScope measures some things at first contact, other radars may measure at ball separation or max deformation. Understanding when/where/how it's measured can make a small difference (for better players this matters more).

As to your original question, @Killa… is he hitting new golf balls? Not practice, not range, not… whatever? A lower compression ball, a range ball, etc. could give lower smash factor numbers because ball speeds could be lower. Without knowing more specifics - is his launch angle lower or higher than normal? Is he taking care to line things up well? Does he get similarly low numbers regardless of the clubhead he uses? - it's tough to say what can be causing these numbers. Has he hit with anything that tells him where he's hitting it on the face, exactly? If you can hit it higher on the face, sometimes that diminished ball speed can be good as the reduction in spin/increase in launch angle lets the ball carry farther.

P.S. The dots are for spin.

[Killa]

1 hour ago, iacas said:

I disagree with that. Trackman and FlightScope are really good about understanding and measuring clubhead and ball speeds. They're great tools for tracking the speed of things, as radar is, and SF is just the division of one number by another, so SF is generally considered very accurate too.

Smash factor is a good way of knowing whether you're achieving a few things:

• Consistency of contact.
• The "proper" amount of shaft lean/AoA/"compression"/etc. on the golf ball (you can over-do it and get low launching balls with less spin and too high a SF).

If you know exactly where you're hitting the ball on the face, that should track pretty well with the smash factor assuming somewhat consistent impact conditions (as a +5 would have).

Now, it's important to know WHEN and WHERE and HOW the various radars measure clubhead speed. For example, is the center of the mass or "blob" of the clubhead measured? If so, the "clubhead speed" will be a bit lower than what the toe of the club is moving, and you can thus get some smash factors above the theoretical 1.5 if you catch the ball on the toe a little. Also, FlightScope measures some things at first contact, other radars may measure at ball separation or max deformation. Understanding when/where/how it's measured can make a small difference (for better players this matters more).

As to your original question, @Killa… is he hitting new golf balls? Not practice, not range, not… whatever? A lower compression ball, a range ball, etc. could give lower smash factor numbers because ball speeds could be lower. Without knowing more specifics - is his launch angle lower or higher than normal? Is he taking care to line things up well? Does he get similarly low numbers regardless of the clubhead he uses? - it's tough to say what can be causing these numbers. Has he hit with anything that tells him where he's hitting it on the face, exactly? If you can hit it higher on the face, sometimes that diminished ball speed can be good as the reduction in spin/increase in launch angle lets the ball carry farther.

P.S. The dots are for spin.

He is hitting premium balls, we tried it today with a variety Taylormade tp5 (it is the “practice” version but it should be the same), a Honma top of the range ball and I gave him one of my (almost brand new) Pro V1x. 
 

The indoor lighting is a bit bad so the club data isn’t showing all the time but we also used foot spray (or dry shampoo) and even on a hit that was basically dead centre he wasn’t getting above 1,45. 
 

I could get some data of some specific hits next week when I go back but he’s playing a g425 lst turned down to 7,5. He is launching it about 11-14 from what I remember, the spin loft on the optimizer is what is recommended. He is hitting it anywhere from +1 to +5 up. His path and swing direction are to the right (he is setting up to the right from the get go) and his face is obviously closed to path. When I had him hit with a face to path that was close to 0° the smash was about 1,45 which was the highest. 
 

He did try a g425 max head today at 9 and 7.5° and it was the same. He also tried my cobra driver but that one is a stiff flex not x and he had trouble swinging and hitting it as well as he did with his shaft (granted he only hit about 5 or 6 balls with it). He will try another g425 lst head from a friend just to make sure there isn’t something wrong with his specific head. 
 

And trying to understand from a physics standpoint I really don’t get how shaft lean has an effect on smash factor other than the obvious change in delivered loft at impact? What am I missing. And if the face to path and aoa/launch are not too much of a glancing blow a sweet spot impact should result in a 1.5 smash regarldess shouldn’t it?

 

We could also gain access to a QC Quad, would that give more accurate/dependable indoor numbers, as like I’ve said, there is no place to hit driver outdoors now and from tomorrow also the shorter ranges should close due to the incoming snow. 

Edited January 5, 2022 by Killa

[iacas]

48 minutes ago, Killa said:

He is hitting premium balls, we tried it today with a variety Taylormade tp5 (it is the “practice” version but it should be the same), a Honma top of the range ball and I gave him one of my (almost brand new) Pro V1x.

Okay.

48 minutes ago, Killa said:

The indoor lighting is a bit bad so the club data isn’t showing all the time but we also used foot spray (or dry shampoo) and even on a hit that was basically dead centre he wasn’t getting above 1,45.

Lighting has nothing to do with it if you're using a radar, which a TM4 is. They work in the dark.

If it's not getting club data, it could be the club design itself, as the systems won't report data it considers suspect.

For example, we had a Piranha muscleback that wouldn't report data very often, and when it did it was a little goofy. It was reproducible for that club. Weird thing, that, but every other 7I swung by the same person produced weird results. It was just the 6I, and it was just the 6I as swung by Dave with his impact conditions.

It just happened to send back a weird set of waves back to the radar, that made it uncertain enough it wouldn't report.

Could be the same thing here. That's why I asked if him swinging other clubs produces the same results.

48 minutes ago, Killa said:

I could get some data of some specific hits next week when I go back but he’s playing a g425 lst turned down to 7,5. He is launching it about 11-14 from what I remember, the spin loft on the optimizer is what is recommended. He is hitting it anywhere from +1 to +5 up. His path and swing direction are to the right (he is setting up to the right from the get go) and his face is obviously closed to path. When I had him hit with a face to path that was close to 0° the smash was about 1,45 which was the highest.

K.

48 minutes ago, Killa said:

He did try a g425 max head today at 9 and 7.5° and it was the same. He also tried my cobra driver but that one is a stiff flex not x and he had trouble swinging and hitting it as well as he did with his shaft (granted he only hit about 5 or 6 balls with it). He will try another g425 lst head from a friend just to make sure there isn’t something wrong with his specific head.

I'm not even saying it's something wrong with his driver head (though you could hit it, because if the face is somehow dead a little, maybe that would show that). Heck, for all you know there's a small crack or something?

48 minutes ago, Killa said:

And trying to understand from a physics standpoint I really don’t get how shaft lean has an effect on smash factor other than the obvious change in delivered loft at impact?

That's how, the bold. Yeah.

48 minutes ago, Killa said:

And if the face to path and aoa/launch are not too much of a glancing blow a sweet spot impact should result in a 1.5 smash regarldess shouldn’t it?

The theoretical max is 1.5, but I've already said you can get 1.51 or even 1.53 depending on a few things.

That section was more general, like talking about using other numbers to practice whatever, not just driving.

48 minutes ago, Killa said:

We could also gain access to a QC Quad, would that give more accurate/dependable indoor numbers, as like I’ve said, there is no place to hit driver outdoors now and from tomorrow also the shorter ranges should close due to the incoming snow. 

I think it generally rates things a bit higher or lower (I can't remember which) because of how it measures. Like I said above, they might all measure slightly different points at slightly different times. The point is to remain "consistent" with one that you understand.

For ball speed/clubhead speed, indoors or out is irrelevant (unless the player swings differently indoors vs. outdoors or something else). Ball speed is captured almost immediately. It has to be - it's slowing down every moment after it leaves the face.

[ChetlovesMer]

@Killa

You may want to read this:

Why you shouldn't fixate on this buzzy golf metric during driver testing

---

Marty Jertson, Ping Golf's VP of performance and fitting, makes a case for why you should stop worrying about the smash factor metric during testing.

 

[iacas]

14 minutes ago, ChetlovesMer said:

@Killa

You may want to read this:

Why you shouldn't fixate on this buzzy golf metric during driver testing

---

Marty Jertson, Ping Golf's VP of performance and fitting, makes a case for why you should stop worrying about the smash factor metric during testing.

 

A quote from there:

In fact, 18 months ago, Ping stopped using the launch monitor metric during fittings after TrackMan’s radar-based device had trouble picking up the middle of the G410 driver head Jertson helped create, before shifting positions to oversee performance and fitting at Ping. 

“Radar signals bounce off drivers differently,” Jertson told GOLF.com. “With G410, the TrackMan is bascially confused and thinks the center is closer to the toe. Because the toe is going faster than the heel, it artificially enhances the clubhead speed. Looking at ball speed, ours is going to be higher.”

Like I said… 🙂 And…

“Measurement devices don’t measure speed in the same place,” he said. “A camera-based unit measures the face, and a radar-based unit tries to measure the middle of the club. If you’re measuring it two different ways, the values are going to be different. The heel and toe are traveling at different speeds.”

So… if he's consistently getting the same numbers, and hitting it well, case solved, perhaps.

[Killa]

1 hour ago, iacas said:

Lighting has nothing to do with it if you're using a radar, which a TM4 is. They work in the dark.

Thanks for all. I’m just gonna elaborate on why I posted about lighting - the trackman itself sends an error about not being able to determine the correct impact location due to insufficient (could be that a different wording is used cannot remember exactly) lighting conditions. 

1 hour ago, ChetlovesMer said:

@Killa

You may want to read this:

Why you shouldn't fixate on this buzzy golf metric during driver testing

---

Marty Jertson, Ping Golf's VP of performance and fitting, makes a case for why you should stop worrying about the smash factor metric during testing.

 

It’s interesting that it’s from a Ping VP and we are talking about Ping drivers here.