McNasty Posted February 25, 2005 Share Posted February 25, 2005 Just wondering if anyone on here has any kind of expertise in this arena. I only have about $1000 to spend, so I was hoping someone, maybe with kids who play softball/baseball, could help me out on the best one to buy. Anyone? Quote Link to comment Share on other sites More sharing options...
Vote Quimby2 Posted February 25, 2005 Share Posted February 25, 2005 Quote Link to comment Share on other sites More sharing options...
TimC Posted February 25, 2005 Share Posted February 25, 2005 I've heard rumors some dent after only a couple of hits....probably want to avoid those, but I couldn't tell you the brand. If we only had someone with experience in that here.... Is your kid on the all-star team? Quote Link to comment Share on other sites More sharing options...
sunysteelfly76 Posted February 25, 2005 Share Posted February 25, 2005 (edited) I'm sure Blitz could help if he were around. Edited February 25, 2005 by sunysteelfly76 Quote Link to comment Share on other sites More sharing options...
skylive5 Posted February 25, 2005 Share Posted February 25, 2005 Demarini Vexxum Softball Bat $159.00 Quote Link to comment Share on other sites More sharing options...
Piranha Posted February 25, 2005 Share Posted February 25, 2005 $1000 for a bat?? I have to buy a bat for my daughter (10) for softball this year. No way am I spending even close to that Quote Link to comment Share on other sites More sharing options...
Hugh 0ne Posted February 25, 2005 Share Posted February 25, 2005 I'm sure Blitz could help if he were around. 711756[/snapback] Couldn't get one by Sunysteelfly, he's a sharp one. Quote Link to comment Share on other sites More sharing options...
skylive5 Posted February 25, 2005 Share Posted February 25, 2005 Guess maybe I should have asked... Is this for home protection or playing softball? Quote Link to comment Share on other sites More sharing options...
McNasty Posted February 25, 2005 Author Share Posted February 25, 2005 I've heard rumors some dent after only a couple of hits....probably want to avoid those, but I couldn't tell you the brand. If we only had someone with experience in that here.... Is your kid on the all-star team? 711755[/snapback] Why, no, he's not. But, I sure would love to hear some stories about kids that do play for an All Star team. Quote Link to comment Share on other sites More sharing options...
Savage Beatings Posted February 25, 2005 Share Posted February 25, 2005 I keep a 24 inch, 14 ounce, aluminum kid's bat named "Venom" next to my bed for home protection. Since my gun is in the safe, this makes for some easy access bad-assification! Other than that... nope. Quote Link to comment Share on other sites More sharing options...
TimC Posted February 25, 2005 Share Posted February 25, 2005 Why, no, he's not. But, I sure would love to hear some stories about kids that do play for an All Star team. 711770[/snapback] Yeah, me too. Really long stories about them. Quote Link to comment Share on other sites More sharing options...
Blitz and Shins Posted February 25, 2005 Share Posted February 25, 2005 The design of baseball and softball bats has been an ongoing process since the inception of the game in the early 19th century. Until the early 1970's, the only material to be used was wood and the potential for design improvements was limited because they involved changing the physical dimensions of the bat. Also, most of the changes were initiated by the player and were carried out by local craftsmen in wood shops. However, with the introduction of hollow-wall aluminum bats in the 1970's and other metal alloys as well as composite materials since then, the potential for applying relevant mechanical principles to improve the performance characteristics of bats has improved dramatically. In recent years a plethora of bats with innovative features have become available to the consumer. Some of these innovations are a result of the research and development efforts of the bat manufacturing industry, often in collaboration with scientists not directly affiliated with the industry, while others are a result of flawed ideas that are not completely thought through. Braham (1997) provides a recent, up-to-date summary of recent innovations by the leading bat manufacturers, but an evaluation of the claims of these products using relevant criteria is lacking. The purpose of this paper is to provide a scientific basis and a focus for examining and developing new bat design features. The paper will provide an overview of the factors that are relevant to the design of baseball and softball bats, including related theoretical and empirical studies. Factors relevant to the design of baseball and softball bats When developing or evaluating a design feature of a baseball or softball bat, the following factors must be considered: (1) the manner in which the bat is swung and forces are transmitted to the bat during the swing, (2) the constraints resulting from rules in the particular sport, and (3) the relevant properties of the bat. I will review each of these general factors in detail, making reference to related scientific literature. Characteristics of batting relevant to bat design Baseball and softball batting is a two-handed sidearm striking skill with the bat held near one end and swung as a physical pendulum. Power hitters attempt to impart maximum velocity to the impacted ball in the desired direction by generating maximum linear velocity of the impacting part of the bat to the ball. The motion of the bat is predominantly in the horizontal plane and the rotation axis ranges from .15 to.20 m off the knob end of the bat toward the hitter's body during the swing. During the swing, the maximum linear (COP) and rotational velocity of the bat is approximately 33 m/s and 36 r/s, respectively, for college females and 38 m/s and 44 r/s, respectively, for college males. Because the primary goal of the power swing is to maximize bat velocity on impact, it is somewhat surprising that maximum bat velocity has repeatedly been found at from .01 to .05 s prior to impact (Shapiro, 1974; McIntyre & Pfautsch, 1982; Messier & Owen, 1984; Spragg, 1986). While this finding has been reported in the scientific literature frequently, a plausible explanation of the reason has not been found. A review of the elastic properties of the bat (appearing later in this paper) and the characteristics of the swing may provide a tenable hypothesis. It is possible that, at the beginning of the swing, torque applied to the bat handle to rotate the bat toward the incoming ball and the inertia of the barrel end of the bat cause the bat to bend, with the barrel of the bat lagging behind. This bending mode, usually referred to as the diving board mode , would begin to release when the rotational acceleration of the bat begins to drop. It is conjectured that the elite hitter learns through trial and error to adopt a bat and swing that are matched such that the velocity of the impact point of the bat is maximized at impact. To accomplish this end, accelerating forces would be reduced quickly at either 1/4 or 1 3/4 of the period of oscillation of the diving board mode. For example, if the fundamental, diving board mode of a bat is 25 Hz, then the period of oscillation is 40 ms. For the hitter to take advantage of this elastic behavior, this bending mode would need to be "released" at approximately 10 or 70 ms prior to impact. While this characteristic of the skilled golf swing has been empirically verified (Cochran & Stobbs, 1986), no empirical data in support of this hypothesis applied to softball or baseball bats have been found. Rules most relevant to bat design The rules regarding baseball bat characteristics are different from those regarding softball bats. Also, rules are different for different genders and different levels of play. For adult males, the maximum baseball and softball bat barrel size is 2.25 and 2.75 in (.057 and .070 m), respectively. The maximum bat length is 42 and 34 inches (1.067 and .864 m) for baseball and softball, respectively, while the maximum softball bat weight is 38 oz (10.569 N). There is no maximum baseball bat weight. All bats used in professional baseball must be made of wood. The most recent rule, which places an upper limit on the coefficient of restitution (Bat Performance Factor) for bats at different levels and types of play, is having a tremendous impact on the direction of bat design activity. Bat performance factor will be discussed in greater detail later in this paper. Inertial and vibrational properties relevant to bat design Several inertial and vibrational properties of the bat are relevant to its effective use: (1) mass, (2) moment of inertia, (3) coefficient of restitution, (4) location of node of the fundamental vibration node, and (5) center of percussion location. Mass and moment of inertia determine the amount of effort required to swing the bat. There is an inverse relationship between bat linear and angular acceleration and mass and moment of inertia, respectively, for a given linear and angular impulse (integral of force/torque and time). Thus, the more mass and/or moment of inertia, the more impulse required to produce a given change in bat speed or direction. In other words, greater mass and moment of inertia compromise the hitter's ability to control the path of the bat as it moves toward the ball as well as to generate bat velocity during the swing. Theoretical models of the relationship between mass and impact parameters indicate that lighter bats than have been used by most skilled players would be more effective (Kirkpatrick, 1963; Adair, 1990). In a study which sought to empirically determine an individual's ideal bat, this concept was supported (Bahill & Karnavas, 1991). Furthermore, bats now used by elite softball and baseball players are much lighter than they were 10 years ago. Bat manufacturers and retailers do not provide moment of inertia measurements with their products; however, moment of inertia is a critical design parameter and is also used to develop bat selection guidelines. When the ball and bat are impacted, during impact the bat behaves in some respects as a physical pendulum and in some respects as an elastic body. Taking both rigid-body and elastic properties into consideration, the best part of the bat on which to hit the ball is called the "sweet spot". The "sweet spot" is a general, nonscientific term, that means that the best overall results are obtained from impacts on this point. In other words, impacts on the sweet spot feel best to the hitter and results in imparting velocity to the ball are best. Or, in more precise terms, the sweet spot is the impact location where the transfer of energy from the bat to the ball is maximal while the transfer of energy to the hands is minimal. On closer examination, four parameters have been identified as having an effect on the "sweetness" (liveliness) and location of the sweet spot: (1) center of percussion (COP), (2) node of the fundamental vibrational mode, (3) coefficient of restitution, and (4) the maximum "power" point. Center of percussion. When the ball hits the bat at the center of percussion (COP), there is no reaction impulse (shock) at the axis. The impact axis for bats has been shown to be the point under the first knuckle of the top hand (Plagenhoef, 1971; Noble, 1983). Thus, COP impacts are more comfortable than at other locations because there is no painful impact "shock" that is experienced during impacts at other locations. The distance from the impact axis to the COP of a bat can be found from the following equation: COPdist = T2g/42 = .2483877*T2 (units in meters) where T is the period of one oscillation when the bat is suspended from the axis, and g is the gravitational constant in meters. The COP has been demonstrated to be the impact location producing the greatest post-impact velocity with stationary bats (Weyrich, Messier, Ruhmann, & Berry, 1989). Another empirical study involving 18 elite slow-pitch softball hitters reported a correlation of .58 between the perceived location of the sweet spot and the COP. Thus, COP location explained 33% of the variability in perceived sweet spot impact location (Noble, 1983). Brody developed a theoretical construct for determining the impact location of a swinging bat with a pitched ball that would result in greatest postimpact ball velocity (Brody, 1986). This location was not on the COP, but was a function of the relative velocity and mass of the ball and bat as well as the inertial properties of the bat. In an early study (Bryant, Bryant, Chen, & Krahenbuhl, 1977) comparing the dynamic and performance characteristics of aluminum and wood bats, data were reported showing an impact area of several cm in length on hollow-wall aluminum bats where there was zero-order reaction impulse while reaction impulse on wood bats was a direct linear of function of distance from the COP. However, a later study by Noble and Eck (Noble & Eck, 1986) presented a theoretical construct and empirical data demonstrating that, assuming the bat is rigid during impact, reaction impulse is a direct linear function of the distance of the impact from the COP (Figure 1). Also, the slope of the regression line of impact reaction impulse on impact-COP distance is a direct linear function of the distance of the COP from the impact axis (Figure 2). In other words, the greater the distance of the COP from the hands, the smaller the reaction impulse resulting from an impact of a given distance from the COP. This study also demonstrated that the distance of the COP from the axis was: COP = I/Mr where I = moment of inertia about the axis, M = the total bat mass, and r = distance from the axis to the center of mass. Strategies were later presented for systematically displacing the location of the COP (Noble & Eck, 1985) by placing mass at various locations along the longitudinal axis of the bat. While these strategies were effective in displacing the COP to a more distal location on the bat, this "improvement" did not enjoy wide acceptance by the players because of the greater excitation of the fundamental vibrational mode resulting from COP impacts (Noble & Walker, 1994b). Quote Link to comment Share on other sites More sharing options...
sunysteelfly76 Posted February 25, 2005 Share Posted February 25, 2005 Quote Link to comment Share on other sites More sharing options...
Blitz and Shins Posted February 25, 2005 Share Posted February 25, 2005 Just a few thoughts off the top of my head. I gotta roll guys, I have a bible study/dojo seminar kicking off in thirty minutes, but have to go kick a few inadequate girls off my daughters softball team first. Catch you later. Quote Link to comment Share on other sites More sharing options...
T_bone65 Posted February 25, 2005 Share Posted February 25, 2005 The design of baseball and softball bats has been an ongoing process since the inception of the game in the early 19th century. Until the early 1970's, the only material to be used was wood and the potential for design improvements was limited because they involved changing the physical dimensions of the bat. Also, most of the changes were initiated by the player and were carried out by local craftsmen in wood shops. However, with the introduction of hollow-wall aluminum bats in the 1970's and other metal alloys as well as composite materials since then, the potential for applying relevant mechanical principles to improve the performance characteristics of bats has improved dramatically. In recent years a plethora of bats with innovative features have become available to the consumer. Some of these innovations are a result of the research and development efforts of the bat manufacturing industry, often in collaboration with scientists not directly affiliated with the industry, while others are a result of flawed ideas that are not completely thought through. Braham (1997) provides a recent, up-to-date summary of recent innovations by the leading bat manufacturers, but an evaluation of the claims of these products using relevant criteria is lacking. The purpose of this paper is to provide a scientific basis and a focus for examining and developing new bat design features. The paper will provide an overview of the factors that are relevant to the design of baseball and softball bats, including related theoretical and empirical studies.Factors relevant to the design of baseball and softball bats When developing or evaluating a design feature of a baseball or softball bat, the following factors must be considered: (1) the manner in which the bat is swung and forces are transmitted to the bat during the swing, (2) the constraints resulting from rules in the particular sport, and (3) the relevant properties of the bat. I will review each of these general factors in detail, making reference to related scientific literature. Characteristics of batting relevant to bat design Baseball and softball batting is a two-handed sidearm striking skill with the bat held near one end and swung as a physical pendulum. Power hitters attempt to impart maximum velocity to the impacted ball in the desired direction by generating maximum linear velocity of the impacting part of the bat to the ball. The motion of the bat is predominantly in the horizontal plane and the rotation axis ranges from .15 to.20 m off the knob end of the bat toward the hitter's body during the swing. During the swing, the maximum linear (COP) and rotational velocity of the bat is approximately 33 m/s and 36 r/s, respectively, for college females and 38 m/s and 44 r/s, respectively, for college males. Because the primary goal of the power swing is to maximize bat velocity on impact, it is somewhat surprising that maximum bat velocity has repeatedly been found at from .01 to .05 s prior to impact (Shapiro, 1974; McIntyre & Pfautsch, 1982; Messier & Owen, 1984; Spragg, 1986). While this finding has been reported in the scientific literature frequently, a plausible explanation of the reason has not been found. A review of the elastic properties of the bat (appearing later in this paper) and the characteristics of the swing may provide a tenable hypothesis. It is possible that, at the beginning of the swing, torque applied to the bat handle to rotate the bat toward the incoming ball and the inertia of the barrel end of the bat cause the bat to bend, with the barrel of the bat lagging behind. This bending mode, usually referred to as the diving board mode , would begin to release when the rotational acceleration of the bat begins to drop. It is conjectured that the elite hitter learns through trial and error to adopt a bat and swing that are matched such that the velocity of the impact point of the bat is maximized at impact. To accomplish this end, accelerating forces would be reduced quickly at either 1/4 or 1 3/4 of the period of oscillation of the diving board mode. For example, if the fundamental, diving board mode of a bat is 25 Hz, then the period of oscillation is 40 ms. For the hitter to take advantage of this elastic behavior, this bending mode would need to be "released" at approximately 10 or 70 ms prior to impact. While this characteristic of the skilled golf swing has been empirically verified (Cochran & Stobbs, 1986), no empirical data in support of this hypothesis applied to softball or baseball bats have been found. Rules most relevant to bat design The rules regarding baseball bat characteristics are different from those regarding softball bats. Also, rules are different for different genders and different levels of play. For adult males, the maximum baseball and softball bat barrel size is 2.25 and 2.75 in (.057 and .070 m), respectively. The maximum bat length is 42 and 34 inches (1.067 and .864 m) for baseball and softball, respectively, while the maximum softball bat weight is 38 oz (10.569 N). There is no maximum baseball bat weight. All bats used in professional baseball must be made of wood. The most recent rule, which places an upper limit on the coefficient of restitution (Bat Performance Factor) for bats at different levels and types of play, is having a tremendous impact on the direction of bat design activity. Bat performance factor will be discussed in greater detail later in this paper. Inertial and vibrational properties relevant to bat design Several inertial and vibrational properties of the bat are relevant to its effective use: (1) mass, (2) moment of inertia, (3) coefficient of restitution, (4) location of node of the fundamental vibration node, and (5) center of percussion location. Mass and moment of inertia determine the amount of effort required to swing the bat. There is an inverse relationship between bat linear and angular acceleration and mass and moment of inertia, respectively, for a given linear and angular impulse (integral of force/torque and time). Thus, the more mass and/or moment of inertia, the more impulse required to produce a given change in bat speed or direction. In other words, greater mass and moment of inertia compromise the hitter's ability to control the path of the bat as it moves toward the ball as well as to generate bat velocity during the swing. Theoretical models of the relationship between mass and impact parameters indicate that lighter bats than have been used by most skilled players would be more effective (Kirkpatrick, 1963; Adair, 1990). In a study which sought to empirically determine an individual's ideal bat, this concept was supported (Bahill & Karnavas, 1991). Furthermore, bats now used by elite softball and baseball players are much lighter than they were 10 years ago. Bat manufacturers and retailers do not provide moment of inertia measurements with their products; however, moment of inertia is a critical design parameter and is also used to develop bat selection guidelines. When the ball and bat are impacted, during impact the bat behaves in some respects as a physical pendulum and in some respects as an elastic body. Taking both rigid-body and elastic properties into consideration, the best part of the bat on which to hit the ball is called the "sweet spot". The "sweet spot" is a general, nonscientific term, that means that the best overall results are obtained from impacts on this point. In other words, impacts on the sweet spot feel best to the hitter and results in imparting velocity to the ball are best. Or, in more precise terms, the sweet spot is the impact location where the transfer of energy from the bat to the ball is maximal while the transfer of energy to the hands is minimal. On closer examination, four parameters have been identified as having an effect on the "sweetness" (liveliness) and location of the sweet spot: (1) center of percussion (COP), (2) node of the fundamental vibrational mode, (3) coefficient of restitution, and (4) the maximum "power" point. Center of percussion. When the ball hits the bat at the center of percussion (COP), there is no reaction impulse (shock) at the axis. The impact axis for bats has been shown to be the point under the first knuckle of the top hand (Plagenhoef, 1971; Noble, 1983). Thus, COP impacts are more comfortable than at other locations because there is no painful impact "shock" that is experienced during impacts at other locations. The distance from the impact axis to the COP of a bat can be found from the following equation: COPdist = T2g/42 = .2483877*T2 (units in meters) where T is the period of one oscillation when the bat is suspended from the axis, and g is the gravitational constant in meters. The COP has been demonstrated to be the impact location producing the greatest post-impact velocity with stationary bats (Weyrich, Messier, Ruhmann, & Berry, 1989). Another empirical study involving 18 elite slow-pitch softball hitters reported a correlation of .58 between the perceived location of the sweet spot and the COP. Thus, COP location explained 33% of the variability in perceived sweet spot impact location (Noble, 1983). Brody developed a theoretical construct for determining the impact location of a swinging bat with a pitched ball that would result in greatest postimpact ball velocity (Brody, 1986). This location was not on the COP, but was a function of the relative velocity and mass of the ball and bat as well as the inertial properties of the bat. In an early study (Bryant, Bryant, Chen, & Krahenbuhl, 1977) comparing the dynamic and performance characteristics of aluminum and wood bats, data were reported showing an impact area of several cm in length on hollow-wall aluminum bats where there was zero-order reaction impulse while reaction impulse on wood bats was a direct linear of function of distance from the COP. However, a later study by Noble and Eck (Noble & Eck, 1986) presented a theoretical construct and empirical data demonstrating that, assuming the bat is rigid during impact, reaction impulse is a direct linear function of the distance of the impact from the COP (Figure 1). Also, the slope of the regression line of impact reaction impulse on impact-COP distance is a direct linear function of the distance of the COP from the impact axis (Figure 2). In other words, the greater the distance of the COP from the hands, the smaller the reaction impulse resulting from an impact of a given distance from the COP. This study also demonstrated that the distance of the COP from the axis was: COP = I/Mr where I = moment of inertia about the axis, M = the total bat mass, and r = distance from the axis to the center of mass. Strategies were later presented for systematically displacing the location of the COP (Noble & Eck, 1985) by placing mass at various locations along the longitudinal axis of the bat. While these strategies were effective in displacing the COP to a more distal location on the bat, this "improvement" did not enjoy wide acceptance by the players because of the greater excitation of the fundamental vibrational mode resulting from COP impacts (Noble & Walker, 1994b). 711805[/snapback] I think that is long enough to suffice Quote Link to comment Share on other sites More sharing options...
Chargerz Posted February 25, 2005 Share Posted February 25, 2005 Did I just see what I think I saw??? Quote Link to comment Share on other sites More sharing options...
Puddy Posted February 25, 2005 Share Posted February 25, 2005 Guess who's back, back again.. If he continues with this alias, he'll never reach 25k.. Quote Link to comment Share on other sites More sharing options...
Czarina Posted February 25, 2005 Share Posted February 25, 2005 Quote Link to comment Share on other sites More sharing options...
georgemoe Posted February 25, 2005 Share Posted February 25, 2005 And I thought he was gone forever. Quote Link to comment Share on other sites More sharing options...
McNasty Posted February 25, 2005 Author Share Posted February 25, 2005 Ahhh, it's almost like having him back. Major props to whoever that is. Quote Link to comment Share on other sites More sharing options...
Piranha Posted February 25, 2005 Share Posted February 25, 2005 I think your username implodes when you hit 25k and you have to make up a new one Quote Link to comment Share on other sites More sharing options...
Chavez Posted February 25, 2005 Share Posted February 25, 2005 If that were the real Blitz, he'd have taken credit for the long article. And been more condescending that EVERYONE oughta know all about softball bats. Quote Link to comment Share on other sites More sharing options...
Big John Posted February 26, 2005 Share Posted February 26, 2005 For protection, make sure it has a lot of splinters for added effect. (but not on the handle) Quote Link to comment Share on other sites More sharing options...
Donutrun Jellies Posted February 26, 2005 Share Posted February 26, 2005 Slowpitch? Can't help you. Fastpitch? Ahhhh .... $175 to $300 will bring you more than enough bat for levels up through Div 1 Collegiate play ... The real key is to get one that fits the batter ... her height/weight/age/skill all play a difference and it's amazing how a hitter who can make solid contact with a 32/20 can't hit with a 32/24, despite some Dad telling her that the added weight will do her good in terms of increased power ... Bah. Forget ego, get the specs that fit the batter and let solid contact and bat speed do the rest. Remember -- the fastpitch swing is not the baseball swing ... and a fastpitch bat is not a baseball bat. My daughter and her teammates have had good results with the higher end Eastons and Louisvilles ... we've been curious about Miken and Demarini. Quote Link to comment Share on other sites More sharing options...
frenzal rhomb Posted February 26, 2005 Share Posted February 26, 2005 Make sure the bat is ASA certified. The ASA has gone about banning certain bats due to how quickly the ball travels off of it. Quote Link to comment Share on other sites More sharing options...
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