ohplease
03-03-2005, 02:10 PM
How do I hit a heavy ball? Can lead tape help? How much weight should I add? Where should I put it?
I got tired of seeing these questions, so I'm providing a solution. First, some background: maximizing racket (or bat or golf club or even sword) impact is all about momentum transfer. Outside of strings or stiffness - for efficient energy transfer, you can either swing faster or swing more mass or both. Of course, for any given player, there will be an ideal racket mass such that they're still able to swing it at a speed that maximizes momentum transfer.
But what of the racket mass? Unless you strike exactly at the center of mass (or balance point), the amount of racket mass involved in the transfer will be some fraction less than the total. Call it the effective or apparent mass at contact. The closer the balance point or center of gravity is to the point of contact - the larger the fraction of total mass involved in the strike. Think hammer weighted frames. At their respective sweet spots, here are some of the frames with the most apparent mass at contact from the last few years: Aerotour Pro Ltd., M Fil 3 Hundred, Catapult 10, Aerotour Pro Ltd. +, Super Revelation 108, Pro Exreme FT, T Fight 315, 200G 95 (Tour Specification), 600G I.C.E., T Fight 325.
Ok, so other than maximizing power - what else do we want from a tennis racket? Well, we also want to make sure our arms don't fall off. That means that we want to minimize the amount of force pushing back into our arms at any given impact. In the same way that effective or apparent mass at contact is really about levers and fulcrums and mechanical advantage - the amount of shock at contact really depends on how far away the balance point is from our hand. Further away = more force (hammer weighting, bad), closer = less force (traditional head light balance). Here are some frames whose weighting minimizes shock: Liquidmetal Prestige Mid, Aeropro Control, Tour NXGraphite Mid, Pure Control Team, Tour NXGraphite OS, Hyper Pro Staff 5.0 Stretch MP, Pure Control + Team, Type C/93, Pure Control MP Team
Hm - a conundrum. We want to feel the sensation of a plowing ball strike, but at the same time we don't want cortisone shots. When we consider only weighting and balance, what are some frames that maximize effective mass while minimizing shock due to weighting and balance? Here are some: Aerotour Pro Ltd. +, Liquidmetal Prestige Mid, Tour NXGraphite Mid, Aeropro Control, M Fil 2 Hundred, Pure Control + Team, Aerotour Pro Ltd., Pure Control Team, Pro Staff 6.0 Original 85, Pro Staff Tour 90.
Say your racket isn't in any of those lists - is there a way to play with lead tape such that it could be? If so, maybe you don't want the swing weight or the balance to be any lower or higher than some numbers you have in mind. Maybe you don't want the total mass to be any greater than some target figure. Maybe you want to maximize the apparent mass to swing weight ratio. Maybe you only want lead tape at 3/9/12, or only at the throat, handle, and 10/2.
Before I send you to the tool, some notes: I'm not trying to horn in on the USRSA's action. They've got some great tools and are a fantastic resource - I just felt that none of their tools did quite what I wanted. Consequently, in deference to them, I'm not going to reveal either their (or my) shock or apparent mass formulas - though I will say that it's just simple mechanics and can easily be re-derived, especially if you spend some time reading about swords or baseball/softball bats. And levers - especially levers.
Anyway, here you go: http://specgeek.50megs.com/LeadTapeOptimizationApplet.html
Hopefully it will be useful to somebody out there.
I got tired of seeing these questions, so I'm providing a solution. First, some background: maximizing racket (or bat or golf club or even sword) impact is all about momentum transfer. Outside of strings or stiffness - for efficient energy transfer, you can either swing faster or swing more mass or both. Of course, for any given player, there will be an ideal racket mass such that they're still able to swing it at a speed that maximizes momentum transfer.
But what of the racket mass? Unless you strike exactly at the center of mass (or balance point), the amount of racket mass involved in the transfer will be some fraction less than the total. Call it the effective or apparent mass at contact. The closer the balance point or center of gravity is to the point of contact - the larger the fraction of total mass involved in the strike. Think hammer weighted frames. At their respective sweet spots, here are some of the frames with the most apparent mass at contact from the last few years: Aerotour Pro Ltd., M Fil 3 Hundred, Catapult 10, Aerotour Pro Ltd. +, Super Revelation 108, Pro Exreme FT, T Fight 315, 200G 95 (Tour Specification), 600G I.C.E., T Fight 325.
Ok, so other than maximizing power - what else do we want from a tennis racket? Well, we also want to make sure our arms don't fall off. That means that we want to minimize the amount of force pushing back into our arms at any given impact. In the same way that effective or apparent mass at contact is really about levers and fulcrums and mechanical advantage - the amount of shock at contact really depends on how far away the balance point is from our hand. Further away = more force (hammer weighting, bad), closer = less force (traditional head light balance). Here are some frames whose weighting minimizes shock: Liquidmetal Prestige Mid, Aeropro Control, Tour NXGraphite Mid, Pure Control Team, Tour NXGraphite OS, Hyper Pro Staff 5.0 Stretch MP, Pure Control + Team, Type C/93, Pure Control MP Team
Hm - a conundrum. We want to feel the sensation of a plowing ball strike, but at the same time we don't want cortisone shots. When we consider only weighting and balance, what are some frames that maximize effective mass while minimizing shock due to weighting and balance? Here are some: Aerotour Pro Ltd. +, Liquidmetal Prestige Mid, Tour NXGraphite Mid, Aeropro Control, M Fil 2 Hundred, Pure Control + Team, Aerotour Pro Ltd., Pure Control Team, Pro Staff 6.0 Original 85, Pro Staff Tour 90.
Say your racket isn't in any of those lists - is there a way to play with lead tape such that it could be? If so, maybe you don't want the swing weight or the balance to be any lower or higher than some numbers you have in mind. Maybe you don't want the total mass to be any greater than some target figure. Maybe you want to maximize the apparent mass to swing weight ratio. Maybe you only want lead tape at 3/9/12, or only at the throat, handle, and 10/2.
Before I send you to the tool, some notes: I'm not trying to horn in on the USRSA's action. They've got some great tools and are a fantastic resource - I just felt that none of their tools did quite what I wanted. Consequently, in deference to them, I'm not going to reveal either their (or my) shock or apparent mass formulas - though I will say that it's just simple mechanics and can easily be re-derived, especially if you spend some time reading about swords or baseball/softball bats. And levers - especially levers.
Anyway, here you go: http://specgeek.50megs.com/LeadTapeOptimizationApplet.html
Hopefully it will be useful to somebody out there.