Dynamic Loft vs Clubhead Speed - Tradeoff?

[blehnhard]

Is there and data to suggest that slightly less than a person's maximum clubhead speed can be offset by a certain decrease in dynamic loft?

In other words would a a drive CHS of say 100 mph with a dynamic loft of 10 degrees be as effective distance wise as 105 mph with a dynamic loft of say 12 degrees? Just using the above #s as possible examples for driver.

Could this also apply to irons?

I am basing the above questions on the assumption that a person would generally generate their maximum CHS at "line up" and then striking the ball before line up would have slightly less CHS but could be offset by less dynamic loft.

Thanks,

Bruce

 

[Jim Kobylinski]

Less clubhead speed will create less ball speed. Even if you assume a 1.45ish smash factor, the difference is 145mph vs. ~152mph. 7mph is a lot; the 105mph swing speed would have to be creating really poor launch conditions for the 100mph swing to end up similar distances and/or a very firm fairway

Irons are a different story as you can make up a lot of distance gap from a higher swing speed player by creating a lot less dynamic loft which will create more ball speed and less spin than more dynamic loft; however again depending on the gap in the 2 players swing speed it may or may not be enough to make it up. I will say it's a lot easier to "keep up" with a big hitter with irons because of this than with a driver.

I know back in my heavy delofting iron playing days i could hit similar irons as guys who could blow it past me 30 yards with the driver.

 

[Todd Dugan]

Smash Factor does increase as Spinloft is decreased, all else equal. But it seems as though, with the driver, we reach a point of "diminishing returns". Which remind me, I recently had a 1.52 Smash on TrackMan demo with my driver. I asked the rep abou that and he said 1.52 is the highest possible. But what if I hit with even less Spinloft?

 

[Frans@France]

Smash Factor does increase as Spinloft is decreased, all else equal. But it seems as though, with the driver, we reach a point of "diminishing returns". Which remind me, I recently had a 1.52 Smash on TrackMan demo with my driver. I asked the rep abou that and he said 1.52 is the highest possible. But what if I hit with even less Spinloft?

the 1.52 is because of the "misread" between the real impact speed at impact and the speed difference between toe en heel part of the clubhead.

if you hit it at 100 mph and the ball has 150mph speed you get the famous 1.50 smash. However if that impact was in the direction of the toe then the machine will measure the center speed which is lower, like 99mph. With the ball at 150 and the speed measured at 99 you get a smash of 1.52

http://www.trackman.dk/download/newsletter/newsletter3.pdf Page 3, table 3

 

[Todd Dugan]

the 1.52 is because of the "misread" between the real impact speed at impact and the speed difference between toe en heel part of the clubhead.

if you hit it at 100 mph and the ball has 150mph speed you get the famous 1.50 smash. However if that impact was in the direction of the toe then the machine will measure the center speed which is lower, like 99mph. With the ball at 150 and the speed measured at 99 you get a smash of 1.52

http://www.trackman.dk/download/newsletter/newsletter3.pdf Page 12, table 3

OK. But on a centered impact, at what point does a reduction to Spinloft no longer increase Ball Speed and Smash? (I may need to throw this one directly to Fredrik)

 

[Frans@France]

OK. But on a centered impact, at what point does a reduction to Spinloft no longer increase Ball Speed and Smash? (I may need to throw this one directly to Fredrik)

Page 12 give's you the calculation of smash based on spin lot and weights

( cos (spinloft) ) x (1+cor) = smash
--------------
Ball mass
1+ -------------
club mass


so spin loft 0 would generate the highest possible smash or ball speed however that would also generate no spin. Hence no real lift so no real ball flight!

Just read page 1 where Tuxen explains that spinloft at 8 degree is around "lowest realistic spin loft for a driver."

 

[Todd Dugan]

Thanks, but I don't see any charts on pg. 12 of the newsletter that you linked. Another link?

 

[Frans@France]

Thanks, but I don't see any charts on pg. 12 of the newsletter that you linked. Another link?

sorry page 3 (of 12)

 

[mgranato]

1.495 is the max smash on a .83 COR face for a center hit. Not being extremely familiar with how the USGA measures now (or used to measure), but I don't think loft is a factor in their measurements. That is the theoretical max, but as Frans correctly pointed out, it can be "fooled". Another possibility that I see occasionally with retail heads (which aren't tested individually like tour heads) is that they can have a "hotter" face than .83. Given the spec tolerances we see between actually loft versus stamped loft, it's no wander there are some really hot faces sitting on the shelves out there. The highest I've personally seen is 1.57. There's no accounting for that other than an out of spec spring like effect.

 

[Frans@France]

1.495 is the max smash on a .83 COR face for a center hit. Not being extremely familiar with how the USGA measures now (or used to measure), but I don't think loft is a factor in their measurements. That is the theoretical max, but as Frans correctly pointed out, it can be "fooled". Another possibility that I see occasionally with retail heads (which aren't tested individually like tour heads) is that they can have a "hotter" face than .83. Given the spec tolerances we see between actually loft versus stamped loft, it's no wander there are some really hot faces sitting on the shelves out there. The highest I've personally seen is 1.57. There's no accounting for that other than an out of spec spring like effect.

USGA uses the CT (or dwell time) test now, and yes some heads can be hotter then other however I recall that the first few "white" heads (let's not mention names ) showed some serious "colder" heads

 

[hp12c]

1.495 is the max smash on a .83 COR face for a center hit. Not being extremely familiar with how the USGA measures now (or used to measure), but I don't think loft is a factor in their measurements. That is the theoretical max, but as Frans correctly pointed out, it can be "fooled". Another possibility that I see occasionally with retail heads (which aren't tested individually like tour heads) is that they can have a "hotter" face than .83. Given the spec tolerances we see between actually loft versus stamped loft, it's no wander there are some really hot faces sitting on the shelves out there. The highest I've personally seen is 1.57. There's no accounting for that other than an out of spec spring like effect.

I need to find one of them hot heads!

 

[Virtuoso]

1.495 is the max smash on a .83 COR face for a center hit. Not being extremely familiar with how the USGA measures now (or used to measure), but I don't think loft is a factor in their measurements. That is the theoretical max, but as Frans correctly pointed out, it can be "fooled". Another possibility that I see occasionally with retail heads (which aren't tested individually like tour heads) is that they can have a "hotter" face than .83. Given the spec tolerances we see between actually loft versus stamped loft, it's no wander there are some really hot faces sitting on the shelves out there. The highest I've personally seen is 1.57. There's no accounting for that other than an out of spec spring like effect.

It's all about tranferring energy. The clubhead has a certain amount of kinetic energy. Even at .83 COR it's very difficult for guys with high head speed to achieve 1.50 (even on a dead center cg hit) because of how much they compress the ball. When you squish the ball, you lose a lot of energy to heat and noise--there is less available for ball speed and ball spin. On the other hand, a little old lady with no speed can acheive 1.53 with a .83 COR head (because the old COR test uesd to be at 100 mph).

Loft obviously plays a huge role. It creates a more "glancing" blow. You save energy because of less heat and noise, but you lose energy to spin. Not a bad thing because you need a certain amount of spin for lift, but your "smash factor" doesn't look as pretty.

 

[mgranato]

USGA uses the CT (or dwell time) test now, and yes some heads can be hotter then other however I recall that the first few "white" heads (let's not mention names ) showed some serious "colder" heads

When I was doing fittings for Cleveland, we LOVED to see someone come in with one of the first gen white heads.