View Full Version : How much does SW decrease by shortening?

01-15-2012, 10:37 PM
By 1/4 and also 5/8. I saw the info in a thread sometime ago, but can't seem to find it again. Thanks for the help.

Edit: I found that it was 25 units/quarter inch. How about balance and weight changes?

01-16-2012, 10:51 AM
About 24 units per half inch, 12 per quarter, 6 per eighth.

01-16-2012, 06:06 PM
Each 0.5" will decrease SW by 16-20 units for most racquets. This range will cover 90% of the racquets out there.

It can easily be calculated more closely with the parallel axis theorem:

SW' = SW + M(x^2 + 20x - 2Rx)
SW' = new swingweight
SW = startign swingweight
M = racquet mass (in kg)
x = amount shortened (in cm)
R = starting balance (in cm)

For a 27" racquet starting with 11.2 oz. (0.317kg), 13" balance (33cm), and 330 SW, the new swingweight after shortening to 26.5" (x = 0.5"*2.54 = 1.27cm) will be about 312 (reduced by 18 kg-cm^2). The heavier the starting weight, the more the SW will change.