Same Swingweight, different lead placements?

[CodyZzZ]

For a given racquet, assuming I can maintain the same swingweight but can choose one of the following:
- More lead at 12, less at 3+9
- More lead at 3+9, less at 12

1) Will the balance be different if swingweight stays same?
2) Which one will be objectively easier to swing and generate racquet head speed, or will they be equal because of same swingweight?

Assuming no tinkering with handle or other parts of the racquet.

Great if you can explain with a bit of physics. : )

Thanks!

 

[Imago]

http://twu.tennis-warehouse.com/learning_center/swingweight_calc.php

 

[Zoolander]

Physiks tells me that the further a weight is from the fulcrum, the greater effect it will have. So option 1 will have a more HH balance i guess, albeit marginally.

If the swingweight is the same then the static weight of option 2 will have to be higher to compensate, which for me makes a racquet harder to swing, even given identical swingweights.

Physiks, she does not lie.

 

[Zoolander]

................

 

[Irvin]

Sw is inertia. Inertia is matter ability to remain in it present state. The greater the mass the greater the inertia, for all intents and purposes. The lowest inertia of an object will always be around the center of mass or balance point in a tennis racket. Sw is the inertia measured at a 10 cm point from the butt. You can use the parallel axis theorem to determine the SW knowing the inertia at the COM.

So now you have SW. if any mass is added anywhere you SW will go up. Assume you have a 27” racket and you add 2 grams inside 12. That’s about 58 cm above the 10 cm axis point. The SW will be the distance in cm squared times the mass in Kg. Adding 2 g at 12 will increase SW by (58*58*.002) 6.728 points. And you balance goes up.

 

[Irvin]

Sw is inertia. Inertia is matter ability to remain in it present state. The greater the mass the greater the inertia, for all intents and purposes. The lowest inertia of an object will always be around the center of mass or balance point in a tennis racket. Sw is the inertia measured at a 10 cm point from the butt. You can use the parallel axis theorem to determine the SW knowing the inertia at the COM.

So now you have SW. if any mass is added anywhere you SW will go up. Assume you have a 27” racket and you add 2 grams inside 12. That’s about 58 cm above the 10 cm axis point. The SW will be the distance in cm squared times the mass in Kg. Adding 2 g at 12 will increase SW by (58*58*.002) 6.728 points. And you balance goes up.

 

[CodyZzZ]

Sw is inertia. Inertia is matter ability to remain in it present state. The greater the mass the greater the inertia, for all intents and purposes. The lowest inertia of an object will always be around the center of mass or balance point in a tennis racket. Sw is the inertia measured at a 10 cm point from the butt. You can use the parallel axis theorem to determine the SW knowing the inertia at the COM.

So now you have SW. if any mass is added anywhere you SW will go up. Assume you have a 27” racket and you add 2 grams inside 12. That’s about 58 cm above the 10 cm axis point. The SW will be the distance in cm squared times the mass in Kg. Adding 2 g at 12 will increase SW by (58*58*.002) 6.728 points. And you balance goes up.

Thanks Irvin, I understand the part about adding weight = SW, and further away from balance point = higher SW. If I may clarify, my question is towards whether there is a difference in maneuverability between adding the same amount of SW to 3+9 compared to adding to 12.

 

[CodyZzZ]

Double post, deleted.

 

[Irvin]

Thanks Irvin, I understand the part about adding weight = SW, and further away from balance point = higher SW. If I may clarify, my question is towards whether there is a difference in maneuverability between adding the same amount of SW to 3+9 compared to adding to 12.

Maneuverability is directly related to SW, balance, and total weight. If you add a specific weight at 12 rather than 3&9 the balance will be higher and the SW will be higher. Total weigh will be the same in each racket but higher. All 3 things that can raise maneuverability go up so it will be harder to handle.

 

[bkfinch]

Double post

 

[bkfinch]

In my experience equivalent sw coming from 3/9 placement makes the racket harder to handle because of the twistweight increase. The widest points of the hoop are heavier. If you put lead at 12, you need less mass to increase sw than at 3/9 so if you are looking at it from equivalent sw point of view lead at 12 will always be easier to whip around. Not sure about balance, it may even out I'm not totally sure.


Sent from my iPhone using Tapatalk

 

[bkfinch]

In my experience equivalent sw coming from 3/9 placement makes the racket harder to handle because of the twistweight increase. The widest points of the hoop are heavier. If you put lead at 12, you need less mass to increase sw than at 3/9 so if you are looking at it from equivalent sw point of view lead at 12 will always be easier to whip around. Not sure about balance, it may even out I'm not totally sure.


Sent from my iPhone using Tapatalk

 

[bkfinch]

In my experience equivalent sw coming from 3/9 placement makes the racket harder to handle because of the twistweight increase. The widest points of the hoop are heavier. If you put lead at 12, you need less mass to increase sw than at 3/9 so if you are looking at it from equivalent sw point of view lead at 12 will always be easier to whip around. Not sure about balance, it may even out I'm not totally sure.


Sent from my iPhone using Tapatalk

 

[Imago]

Third time's a charm...

 

[CodyZzZ]

Liking all three lol, thanks @bkfinch . interesting mention on twistweight's impact on maneuverability. I ended up shifting half of the weight from 3&9, cutting that by half, then putting it at 12. The new SW is very similar and specs looks like what I want but will have a go with it on Monday.

 

[Irvin]

For a given racquet, assuming I can maintain the same swingweight but can choose one of the following:
- More lead at 12, less at 3+9
- More lead at 3+9, less at 12

1) Will the balance be different if swingweight stays same?
2) Which one will be objectively easier to swing and generate racquet head speed, or will they be equal because of same swingweight?

It may be easier for you to understand if we talk about actual numbers. What SW, weight, and balance do you have now and what are you looking for?

EDIT: Also measure the distance from the butt to 3&9 and 12 positions on the centerline going up the frame. And measure the perpendicular distance from the 3&9 position to the centerline.