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Old 09-25-2006, 05:48 PM   #1
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Join Date: Dec 2005
Location: Detroit Area, MI
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Default Racquet Mod Formulas: Matching Specs

Roughly two weeks ago, I posted a thread with an emberassingly simple system for attaining a given balance point, with given weights. Well, the original idea behind it's complete, and here it is:

Given a final weight, balance, swingweight, and one (1) added mass, it will spit out the location of the necessary added masses, as well as the added weight of the other concentrated mass. Checked with Steve H.'s original Racquet Mod excel sheet. All figures in metrics.

Now, without further ado, the spreadsheet.

The Spreadsheet has been updated to include some traits I thought important.

If you look a few replies down (the third, I believe) then you'll see that Travler suggested a few things I should add, and this is one: Instructions.

Begin by plugging in the values for the top three white squares, with the labelled amounts for the racquet you're using. For my DNX 10, I labeled them.


In that order. Do not add units! If you don't know off hand the specifications of your racquet, then check TW's info on it.
Next, in the next set of whited-out boxes, enter the intended specifications of your racquet, with all said and done. For instance, to go with the specs in the spreadsheet by default, I wanted to go with the 'Sampras setup' listed by TravlerAjm. That required a weight of 384 g, a 32 cm balance, and a swingweight of 367.
The fourth whited-out box in that section, labeled 'Weight 1 Mass,' you can enter just about any number lower than the total added mass in grams. If you're not sure how much mass you're adding the spreadsheet provides you with that piece of information. What this is, is the amount of weight to add at the first spot, or 'location 1.'

Afterwards, it will spit out a few numbers: The important ones are cells C23 and C24, though future variations on this spreadsheet will make use of the final recoilweight, polarization, and so forth, in a more central role.

A Note On The Effect Of Specifications:
Weight or Mass will change the static weight, and the punch on your volleys, but little else.
Balance will have a distinct effect on the feeling of your racquet, wether it feels like it plows through the ball or gets pushed around by it. This is measured in CM from the butt of the racquet.
Swingweight is a measure of the difficulty of swinging the racquet, but it is also a factor in the power level of the racquet: higher swingweight, higher power.
Recoilweight is a measure of how much the racquet yields to the incoming ball. More means less. A flat hit shouldn't need much of this, due to the 'plowing' nature of the shot, where a windshield-wiper forehand will probably need more considering that it pretty much absorbs the ball's incoming speed.
Effective Mass is a measure of how much mass is used when the racquet hits the ball. It's not intelligible, at this point, but it makes for a good reference point of how much your power will be changed.
Polarization Index is a measure of how spread out your weight is. The higher the polarization index, the spinnier your racquet will tend to be. (Explained in the link)

If either value for 'weight location' comes out as greater than the total length of your racquet, you need to modify your input 'Weight 1 Mass.'
Diablo Tour 93, TNT2 16 @ 56#, Prince DuraRib+
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