AoA and divots

[birly-shirly]

Is there a simple relationship between the two?

In other words, will the same angle of attack with the same club result in the same size/depth of divot?

Or, is it possible to have similar angles of attack which shallow out differently through the ball - one taking a hefty divot and the other just brushing the grass?

I'm not talking about different turf conditions, clubs or sole designs here - assume these remain the same.

Thanks for any thoughts

 

[Frans@France]

You could even have a very negative AoA and still top the ball. The AoA is just the direction of the clubhead and not an indication how low/high above level the low point really is.

 

[birly-shirly]

Sorry - but of course you're right Frans. I should have added as an assumption that the strike is good in both cases.

 

[Frans@France]

My guess is that the divot will then depend mostly on the amount of forward shaft lean. Seems to me that the amount of forward shaft lean allows the low point of the swing path to be just that longer/flatter then with less or no shaft lean.
- Also more shaft lean would create more of a digging leading edge due to the de-lofting of the club.
- forward shaft lean/ delofting would create more compression and create more clubhead lag after impact en just before divot contact.

 

[birly-shirly]

OK - so is the amount of forward shaft lean independent of the AoA? In other words, could I have a relatively steep AoA but not much forward shaft lean, resulting in little or no divot? Or is a very slight divot a reliable indicator of an AoA that is still quite shallow? Shots are not fat.

 

[savydan]

Forward shaft lean is absolutely independent of AoA.

My take would be something like this:

Frans' first statement that technically AoA is not tied to the divot is correct.

If we are swinging on an inclined plane, like Brian's blue plane board, then a more negative AoA, would likely result in a deeper divot.

You would strike the ball as the clubhead is sliding down the plane, then the clubhead would continue on the plane to lowpoint, making a divot before and after lowpoint. We are also assuming, I think reasonably, that the clubhead path is pendulum-like, or close to it.

You could, technically, swing on an inclined plane, and then after impact, the clubhead could continue to China. Then you'd have a deep divot.

But, normally, usually, and "golf-like" swings would pretty much have deeper divots with more negative AoA's. You can't say it absolutely. But on an inclinded plane, with a pendulum arc, with decent contact, I think so.....

 

[birly-shirly]

I would have thought so too - although I'd have also thought that there would be a relationship between forward shaft lean and AoA.

The reason for asking is that I've been practicing with a towel on the ground, about 5" behind the ball. Ball striking has been good - but the drill has certainly made me work on a steeper path into the ball.

I was hoping that the towel would tell me if I was too shallow or if lowpoint was creeping back off the ball - but that hefty divots on the target side of the ball would be my warning that I was overdoing the drill.

Now I'm getting a long iron squarely onto the ball but scarcely any divot. To be honest, I'm a bit surprised not to see more of a divot. I don't really care whether I take a divot with a long iron or not - but I do care about getting too steep and so I was hoping that my divots would provide feedback on this.

I guess I could try moving the towel even closer to the ball - although 5" seems plenty close enough with 4iron or longer.

 

[Jim Kobylinski]

Can more lean sometimes equate to more down? Yes, it can but it isn't an absolute. I strive for foward lean with a shallow angle of attack; the more i do that the better i hit the ball.

 

[Virtuoso]

Can more lean sometimes equate to more down? Yes, it can but it isn't an absolute. I strive for foward lean with a shallow angle of attack; the more i do that the better i hit the ball.

Trevino, one of the best ball-strikers of all time, thought same. But he did occasionally get too steep with the shorter irons. And high long irons were out of the question.