In any game, the equipment players use determines the way the game unfolds. Try to imagine a soccer game played with an American football! Or try playing tennis with the wooden racquets of thirty years ago. Change the equipment, and you discover a very different game. As part of my look at baseball, I decided to examine the tool of the baseball trade: Bats. Perhaps the most crucial and visible tool in baseball is the bat. A bat is the offensive weapon, the tool with which runs are scored.
To understand the history and science of bats, I read a magazine published by Louisville Slugger, in Louisville, Kentucky home of the Hillerich & Bradsby Company, Inc. (also known as H&B), the manufacturers of perhaps America’s most famous bat, the Louisville Slugger. Through the reading I learned how the modern bat came to be, and what it might become. In 1884, John Andrew “Bud” Hillerich played hooky from his father’s woodworking shop and went to a baseball game. There he watched a star player, Pete “The Old Gladiator” Browning, struggling in a batting slump.
After the game, Hillerich invited Browning back to the shop, where they picked out a piece of white ash, and Hillerich began making a bat. They worked late into the night, with Browning giving advice and taking practice swings from time to time. What happened next is legend. The next day, Browning went three-for-three, and soon the new bat was in demand across the league. H&B flourished from there. First called the Falls City Slugger, the new bat was called the Louisville Slugger by 1894.
Though Hillerich’s father thought bats were an insignificant item, and preferred to continue making more dependable items like bedposts and bowling pins, bats became a rapidly growing part of the family business. Just as it was back then, the classic Louisville Slugger bat used by today’s professional players is made from white ash. The wood is specially selected from forests in Pennsylvania and New York. The trees they use must be at least fifty years old before they are harvested. After harvest, the wood is dried for six to eight months to a precise moisture level. The best quality wood s selected for pro bats; the other 90 percent is used for consumer market bats. White ash is used for its combination of hardness, strength, weight, “feel,” and durability. In past years, H&B have made some bats out of hickory. But hickory timber is much heavier than ash, and players today want light bats because they’ve discovered that they can hit the ball farther by swinging the bat fast. So they can’t make the bats out of hickory. Though Babe Ruth, one of the all-time great home-run hitters, used a 42 or a 44 ounce bat, players today use bats that weigh around 32 ounces.
Even sluggers like Mark McGwire and Ken Griffey, Jr. only use 33 ounce bats because they want to generate great bat speed. How do you make a wooden bat you ask. Heres how. The wood is milled into round, 37 inch blanks, or billets, which are shipped to the H&B factory in Louisville. There they are turned on a tracer lathe, using a metal template that guides the lathe’s blades. These templates are set up to the specifications of each pro player. Then the bats are fire-branded with the Louisville Slugger mark. This mark is put on the flat of the wood’s grain, where the bat is weakest.
Players learn to swing with the label facing either up or down, so that they can strike the ball with the edge grain, where the bat is strongest. Hitting on the flat grain will more often than not result in a broken bat. Finally, the bats are dipped into one of several possible water-based “finishes” or varnishes, which gives bats their final color and protective coat. Each player selects the finish they desire, while a few players, such as former Kansas City Royals star George Brett, chose to leave their bats unfinished. Players today may go through as many as six or seven dozen bats in a season. In early years, players used only use ten or twelve bats. ) In fact, one player, Joe Sewell, used the same bat for fourteen years. Joe attributes the increased breakage of bats to the thin-handled, large-barreled design of modern bats, and to the use of ash instead of hickory. A pitch that jams you inside will almost always saw off a modern bat, while an aluminum or old-fashioned hickory bat might produce a base hit. Though the manufacturing process for bats has stayed largely the same, the design of the pro wood bat has changed a great deal since 1884.
The early bats had very little taper, resulting in a bat with a very thick handle and a relatively small barrel. The early bats almost look like someone just took an ax handle and used it for a bat. Modern players want a thin handle and a large barrel, to concentrate the weight of the bat in the hitting area. By major league regulations, bats must be round with a barrel of no more than 2 3/4 inches. They can be up to 42 inches in length; there is no regulation about the bat’s weight. One of the few innovations to the design of the wooden bat is cutting a “cup” out of the end of a bat.
Developed by a pro player named Jose Cardinal in 1972, this “cup” can’t be more than 2 inches in width, and 1 inch deep. The cupped bat allows the bat maker to use a heavier, denser, stronger timber, while still maintaining the desirable bat weight. Recently, Ted Williams visited the Louisville Slugger Company and he said that if he was playing today, all of his bats would be cupped. About half the pro bats made by H&B today are cupped bats. Throughout the history of baseball, players in search of an edge have doctored, or altered, bats in many unusual ways.
The main strategy has been “corking” the bat. Players cut the end of the bat off, drill a hole down into the barrel of the bat, and fill the hole with cork, then glue the end back on. This is an attempt to lighten the bat, and give it more spring or bounce. But really this does nothing advantageous to the bat. In fact, the bat gets weaker, because theyve drilled out the heart of it. You may remember the time when [pro player] Graig Nettles put a bunch of rubber “superballs” inside his bat, and the bat broke, and all the balls spilled out.
Nettles attributes the persistence of corking more to head games between the players than to any advantage a corked bat might have. Players have also been known to rub their bats with ham bones or glass bottles, a process called “boning,” in an attempt to harden the bat. However, this practice doesn’t seem to produce any benefit beyond the psychological either. In early days, some hitters would illegally hammer nails into their bats so that the ball would strike “iron. ” Even if the bat could be made harder, it would only diminish hitting.
Solid wood bats “give” very little in the impact area, and thus they store very little energy. What little they do store, they give back [to the ball] very efficiently. On the other hand, the ball distorts a lot under impact, and is relatively inefficient in giving the energy back. So a harder bat just results in more deformation of the ball, and a lesser hit. The question that come to us next was, but what about a metal bat? The most stunning change in baseball bats in the past thirty years started in the 1970s, when bats made from tubes of aluminum began to appear.
These tubes are machined to vary the wall thickness and the diameter, and produce bats that are light, strong, and hollow, as opposed to the solid wood. At first, the aluminum bat was just a metal copy of a wooden bat. They were just more durable, so they were cheaper to use. But manufacturers and players soon discovered that there were other differences as well. Aluminum bats are quite different than wooden ones. They’re much lighter, more than five ounces. The barrels are bigger, and because they are lighter they can be swung faster than a wooden bat.
In addition, the hardness and resilience of aluminum can result in much greater speeds when the ball comes off the bat. Major League Baseball has required that its players use wooden bats, but the aluminum bat has come to dominate the lower levels of baseball, from Little League to American Legion to the college game. The most significant difference between wooden and aluminum bats is that with an aluminum bat, a phenomenon occurs called the ‘trampoline effect. ‘ The walls of the bat are thin enough that they deform, or flex when the ball hits the bat.
Some of the energy (of the collision) is transferred into the bat instead of the ball. That energy is almost totally elastic; it is given back, or bounces back, almost 100 percent. The energy absorbed when the ball is deformed is almost 75 percent lost to heat, and thus wasted as far as propelling the ball. Because of this trampoline effect, you can hit the ball somewhat faster, and somewhat farther. In fact, when the NCAA approved the use of aluminum bats in 1974, H&B started comparing statistics and found that the team batting averages went up about twenty points, and the home-run production about doubled.
The primary reason that wooden bats are required in the pros is due to this performance difference. The pro leagues want to protect their historical records, and they want the performance of the game to be the result of human ability, rather than the technology of the bats. Ever-increasing performance of metal bats has begun to affect the game at the college level and below. Aluminum bat makers have been exploring stronger and lighter metal alloys. The results include ever-lighter bats with thinner walls, and consequently higher bat speeds and even greater trampoline effects. A ball hit by these bats travels farther and faster.
In addition, H&B has already made a bat called the AirAttack in which a polyurethane bladder is inserted into the center hollow, then filled with pressurized nitrogen gas. The gas pressure in the bladder supports bat walls, pushing them out after they are deformed under impact. This support allows a much thinner wall and a greater trampoline effect. H&B has a softball bat called the Inertia, in which the interior of the bat contains a rolled-up steel spring that does the same thing. Batting averages and home-run production have gone up consistently at the college level as these advances have appeared.
Titanium was used briefly, but it was quickly prohibited because that metal’s combination of high strength, light weight, and elasticity was clearly going to result in shattering all hitting records in all phases of the game. You could actually grab the barrel of the bat in your hands and squeeze, and you could feel the bat give. The trampoline effect was enormous, and though titanium was banned, Louisville Slugger learned a lot about how to make aluminum bats achieve the same effect. Recently, a heated debate has broken out over the widespread use of aluminum bats in ollege leagues. Many in baseball fear that modern technology is creating a “superbat,” which will irrevocably alter the game and endanger players. Indeed, the rules committees are diligently looking at the performance of bats, and they have already put some limits on performance; they may well add more. They are not only concerned about the integrity of the game, the balance between offense and defense, but they are also concerned about safety. The NCAA rules committee has decreed that many modern metal bats are dangerous to players and disruptive to the game.
The high speed of the ball coming off the these metal bats has put pitchers in danger, as a line drive hit at them may be traveling too fast for them to get out of the way. And the energy of a hit ball increases as the square of the velocity, so a fast hit can do more damage. As a result, the NCAA has ordered recently that bat manufacturers alter their designs to make bats heavier, with a smaller barrel. And baseball organizations from college to Little League are considering a return to a “wooden bats only” policy, though the expense of wooden bats may make such a move unfeasible.