By | March 27, 2023

So far we have looked at the process of rolling a composite bat and the equipment used to do the rolling. Now we will take a little look at the beginning of both, and how it has evolved.

Composite Bats

Composite bats were originally introduced to the playing public in the early 80s’, to the slow pitch softball segment of the sport. At the time the aluminum bat was the most popular out selling and out performing the wood bats that had been used up till then. As it turned out the aluminum bat also out performed the new composite bat, so the composite bat did not gain much favor with the players of the game. But in 2001 with advances in technology and materials Louisville Slugger earned the award of “Best Performance” with their newly designed composite bats. And that is when the bat wars started, because in 2002 Miken also came out with their newly designed composite bats. From then till now the technology has grown in leaps and bounds, and all the bat manufactures are producing composite bats. Not only are they using the woven glass fibers as a composite material, they are using carbon, graphite and kevlar to make the new high performance bats. These advances in technology have also brought about rules changes to make sure the safety of the players is maintained.


There are five major advantages to the composite bat over its rivals. They are, swing weight,bending stiffness bending vibration, trampoline effect, and lastly sound. The swing weight is reduced because it is much easier to move the center of the bat mass closer to the handle in the production process of the composite bat. This is also true for the bat stiffness and the handle vibration, because the different types of materials they are able to use. By altering these materials they can alter stiffness and vibration. The trampoline effect can be increased because of the physics of elastic collision, also determined by the application and procedures and application of different materials. And lastly the sound. The composite bat gives a much more solid sound than its aluminum brother.

The Break In

When the composite bat exploded onto the market, after a period of time, it was discovered that with more use the bats actually improved in performance. They hit further, and had less vibration transferred to the handle. Now, the bat manufactures suggest a break in period of 500 to 600 hits before the bat reaches its designed B.E.S.R., or ball exit speed ratio. Back in 2002 this idea was totally new. So if the rules of today state a maximum B.E.S.R. of 98 miles per hour, a new bat fresh out of the wrapper may only have a B.E.S.R. of 92 or 93 mph to allow for the break in process, and the bat reaches its maximum performance. Bat rolling has become popular because it accelerates this process and eliminates a lot of the wear and tear hitting 600 balls puts on a bat.

How Rolling Got Started

In California a guy, probably a machinist, used a metal forming devise called an English Wheel to help his bat perform better. An English Wheel is a large piece of equipment that has two large convex steel wheels, about 8 inchs’ in diameter, set one on top of the other. Used to form metal, these wheels can be brought together using a foot pedal, to determine how much pressure is applied to the metal during the rolling, or forming process. So this guy put his bat between the rollers, moved it in and out, rotated it and continued the process around the barrel of his bat. Thus, perpendicular bat rolling came into being. After this a much smaller devise was made, using nylon rollers. and a clamping devise to apply the needed pressure to loosen the fibers of the bat.

How About Parallel Rolling

In 2006 or 2007 a guy in Michigan introduced the first parallel bat rolling machine.This was more advanced than the perpendicular type rollers. It had two 7 inch polyethylene rollers. set parallel to each other, in a very precise clamping devise. It had four independent clamping adjustments instead of a single central adjuster to control the clamping pressure. The bat was set between the rollers using a register devise, to make certain it was straight, and by turning the rollers and using the 4 fine tune adjusters, a bat barrel was completely rolled in just a few sequences. His devise could, however, also be used to roll the bat in a perpendicular manner, thus having the best of both operations. And thus the parallel rolling machine was introduced.

Other Methods

Before and even after the bat rolling machines became popular there were some other very creative methods used to perform the break in process. They were however not quite as effective. A common bench vise has been used to 안전놀이터 compress and squeeze the bat barrel. It was effective but led to breakage and failure of the bat material, because of lack of consistency. An inventor devised a similar method using a hydraulic car jack set into a clamping devise with similar results. Some have used a heavy mallet to pound the bat barrel, and someone also thought to put a softball on the end of a hammer handle to beat the bat with. In my slow pitch softball playing days, I have seen guys actually hitting a telephone pole, and a large steel fence post covered with a towel, with their bats to try and break them in, or maybe out.

The Evolution

So then we had the dedicated perpendicular, and the new perpendicular or parallel rolling machines. The guys with the perpendicular devises saw they were at a disadvantage and getting left behind, so they redesigned their machines to also be able to do both methods. Some added a second roller to either the top or bottom to make it easier to set the bat parallel to the rollers. They also added a very simplistic handle to the central compression adjuster, and also to roller spinner. So that brings us up to where we are today.

I am sure there will be new devises invented to accelerate the break in process of the composite bat. With changing rules and new bat construction and technology new methods may have to be devised. I already have two new ideas on the drawing board if needed. One I hope will be about half the price of the existing rolling machines, and the other may have to be half again as expensive. I guess we will have to wait and see what happens to the rules and the market.

Leave a Reply

Your email address will not be published. Required fields are marked *