My Study of OBFL versus NBFL

[SocketRocket]

Here's a link showing Tiger's 8-iron striking.

http://thesandtrap.com/t/45647/sweetspot-on-irons-where-the-good-players-hit-it

It would indeed be possible, specially in longish fairways, to sweep and strike at bottom of tho swing and still hit the sweet-spot. The ball is 1.68", so if the sweet spot is 0.84" from bottom of iron (or less), then perfectly feasible, even on tight links courses.

0.84" would be the balls equator. To hit the balls equator without thinning the shaft would need a forward lean of something like 45 deg.

If you take a ball in the flat palm of your hand and place a sand wedge behind it, you will notice if the shaft is set vertical contact is made towards the bottom of the ball just above the leading edge of the clubface. As you lean the shaft forward the impact position moves up the ball and clubface. To hit the sweetspot (around the position shown on Tigers club) you will need something in the region of 10 /15 degrees of forward shaft lean.

OK, if the ball is sat up on long grass then I can see how but on a normal mowed fairway I find it hard to see how you could make contact in the sweetspot without the hands leading and the club still descending at impact.

What do you think?

 

[Patrick57]

OK, if the ball is sat up on long grass then I can see how but on a normal mowed fairway I find it hard to see how you could make contact in the sweetspot without the hands leading and the club still descending at impact.

What do you think?

It's a no brainer, the hands must lead at impact and thus the ball is struck with a downward action.

 

[DaveM]

I think you will find if you place an iron on the ground. So that the sole is parallel to the ground. You will find you have differing degrees of forward lean. More on the short irons less on the middle irons and a slight lean backwards on the long irons. The sweet spot of each iron is positioned so.That as long as the club strikes the ball at the set angle of the club you will contact the sweet spot. It does not matter if you sweep or hit down as long as that angle is maintained you will hit the sweet spot(all things being equal). Even a sweeper like myself will hit a slight divot, even if it only bruises the grass rather than taking a lump out.(After all this happens after impact, or should do).

 

[SocketRocket]

(After all this happens after impact, or should do).

That's right Dave but it does reflect what happened before and at impact as well.

 

[JustOne]

I can't claim to know where the sweetspot is on the face of an iron in terms of height but I do know the higher up the face you hit it the less far it will travel... so if anything you might as well catch it one groove lower... as seems the case on those pics of iron impacts.

 

[DaveM]

That's right Dave but it does reflect what happened before and at impact as well.

Thats true. In my case I'm not very tall with long arms and standard length club. So a sweep is more my normal swing. I have not commented on this thread as such. As it has taken a while to sift out the good from the bad from the total rubbish. Got there in the end lol.:thup:

 

[JustOne]

I have not commented on this thread as such. As it has taken a while to sift out the good from the bad from the total rubbish. Got there in the end lol.:thup:

Try and keep up! LOL

 

[DaveM]

Try and keep up! LOL

Cheeky sod. Bit like my swing. Slow and steady. Or thats what I like to think.

 

[sev112]

Thats true. In my case I'm not very tall with long arms and standard length club. So a sweep is more my normal swing. I have not commented on this thread as such. As it has taken a while to sift out the good from the bad from the total rubbish. Got there in the end lol.:thup:

Dave, for the benefit of us who are not so clear of mind, would you mind summarising which bits were goodm bad and rubbisn ...

 

[Foxholer]

SR,

Please not the 'or less' in my post re the sweetspot that you quoted.

I have no idea where you obtained the 45* value, but it seems way over the top. The 10-15* sounds much more 'normal'.

I believe the only true evidence that there is, or isn't, a downward strike is the fact that there is, or isn't, a divot. No divot means no downward action - or thin contact. Divot (after the ball) means downward swing.

 

[SocketRocket]

SR,

Please not the 'or less' in my post re the sweetspot that you quoted.

I have no idea where you obtained the 45* value, but it seems way over the top. The 10-15* sounds much more 'normal'.

I believe the only true evidence that there is, or isn't, a downward strike is the fact that there is, or isn't, a divot. No divot means no downward action - or thin contact. Divot (after the ball) means downward swing.

Each club is designed with an amount of forward lean to the shaft when the sole is grounded. The shorter the club the more it leans forward so longer clubs do not hit down quite as much and are designed to sweep the ball away, likewise the shorter irons with their forward lean are designed to hit steeper and leave a divot.

If you look at the attached image you will see that to get the clubface to make contact with the ball at its equator it would require a very steep forward lean on the shaft. Without any forward lean it would be impossible to make contact with the sweetspot.



View attachment 2268

 

[Foxholer]

Each club is designed with an amount of forward lean to the shaft when the sole is grounded. The shorter the club the more it leans forward so longer clubs do not hit down quite as much and are designed to sweep the ball away, likewise the shorter irons with their forward lean are designed to hit steeper and leave a divot.

If you look at the attached image you will see that to get the clubface to make contact with the ball at its equator it would require a very steep forward lean on the shaft. Without any forward lean it would be impossible to make contact with the sweetspot.



View attachment 2268

I'd suggest, without knowing the precise amounts, that the slightly greater forward lean (camber?) in the shorter irons is more likely to be because they are shorter, so having the hands in the same position at address and impact - slightly ahead of the ball (or leading) - requires a slightly greater angle for the short irons than the long ones.

How do you explain the divot/no divot situation? It seems pretty compelling (dynamic) evidence and doesn't involve any stats, measurements or pictures that may/may not have be frigged.

I'd actually suspect that even a sweeper/picker actually does hit the ball marginally before bottom of arc, so on the way down, but the compression and rolling of the ball up the club during the few micro-seconds of connection means the sweet-spot is found. Have I answered my own question?

 

[Patrick57]

I'd suggest, without knowing the precise amounts, that the slightly greater forward lean (camber?) in the shorter irons is more likely to be because they are shorter, so having the hands in the same position at address and impact - slightly ahead of the ball (or leading) - requires a slightly greater angle for the short irons than the long ones.

How do you explain the divot/no divot situation? It seems pretty compelling (dynamic) evidence and doesn't involve any stats, measurements or pictures that may/may not have be frigged.

I'd actually suspect that even a sweeper/picker actually does hit the ball marginally before bottom of arc, so on the way down, but the compression and rolling of the ball up the club during the few micro-seconds of connection means the sweet-spot is found. Have I answered my own question?

Yes!

 

[SocketRocket]

I'd suggest, without knowing the precise amounts, that the slightly greater forward lean (camber?) in the shorter irons is more likely to be because they are shorter, so having the hands in the same position at address and impact - slightly ahead of the ball (or leading) - requires a slightly greater angle for the short irons than the long ones.

How do you explain the divot/no divot situation? It seems pretty compelling (dynamic) evidence and doesn't involve any stats, measurements or pictures that may/may not have be frigged.

I'd actually suspect that even a sweeper/picker actually does hit the ball marginally before bottom of arc, so on the way down, but the compression and rolling of the ball up the club during the few micro-seconds of connection means the sweet-spot is found. Have I answered my own question?

Yes, I would go with that. As the hands lead the clubface the swing arc bottom will be ahead making a divot as it bottoms out. Longer clubs have less forward lean designed to the shaft so do not bottom out as far forward.

 

[Patrick57]

Yes, I would go with that. As the hands lead the clubface the swing arc bottom will be ahead making a divot as it bottoms out. Longer clubs have less forward lean designed to the shaft so do not bottom out as far forward.

Can't agree more!