Bat Rolling – The Process
As I have written before, bat rolling is really not that complicated a process. There are however very different methods of carrying out the process. The machine used consists of a pair of urethane rollers. These roller, which can be between 5 and 7 inchs' long, depending on the manufacturer of the machine. Are each fixed to a rigid 5/8 metal shaft. Each end of the shafts are inserted, and secured, in a heavy, sealed, ball bearing. These are in turn secured into the bat clamping devise. Picture a pair of rolling pins set parallel to each other and fastened into the jaws of a large vertical vise.
Your composite bat is inserted between the rollers and secured into the clamping devise. Then in a series of clamping the bat, and turning the rollers to rotate the bat, the bat is compressed to the desired amount by the person you have trusted your bat to. This compression, releases the fibers in the bat laminations' and in turn accelerates the break in process of your bat. Which of course is the objective. If done correctly your bat should perform up to the factory specifications. So you can now get the most from your bat in a short period of time.
Is there a differences
Not all the people rolling bats out there use the same methods or the same rolling devices. There are differing views on both. Some say the bat should be rolled both parallel and perpendicular to the bat barrel, and some say only parallel is necessary. Most agree that parallel rolling gives the most uniform and consistent release of the composite bat fibers. Some also have differing opinions on which type of material the rollers are made of to get the best outcome from the process. It seems all the rollers are made of a very hard urethane material, and the differences make little difference as to final outcome of the rolling process. As far as I have been able to ascertain, though the equipment may be a little different the process they use is pretty much the same. That is because that is what the instruction booklet that came with their machine told them how to to it. I however take a very different, more exacting, scientific approach to the rolling process.
From my experience in machine repair, and high performance motorcycle engine building, I have developed a very precise and much more accurate method of rolling your composite bat. I use specialized equipment to measure the amount of pressure applied to the bat surface, as well as the amount of compression of the bat barrel surface. This allows me to make sure you get the ULTIMATE PERFORMANCE from your bat, because I know exactly what is being done during the rolling process. I have yet to see anyone else out there that has even thought of being as precise as I am.
What Special Equipment
To measure the amount of pressure being applied to the bat surface I use an inch pound torque wrench. This has an analog (or dial) indication display, which give me direct and precise pressure measurements, because it measures the pressure per square inch of surface area. Everyone else just goes by the number of turns to a handle. To measure the amount of deflection(or compression) to the barrel surface I use an analog (or dial) micrometer. This measures in 1/1000 ths' of an inch increments. You can not get much more precise than that. This is also done by the turn of the same handle. Whos' guessing?
Not all composite bats are made the same, which I am sure you are well aware of. Some are more rigid and some more flexible. Some bat barrels are much thicker and respond differently when compressed. This also holds true for the different materials used to construct the bat. There is a great amount of differing science used to construct a bat because the manufactures want their bat to stand out from the rest. Naturally they want you to buy their bat. Price also determines how the bat is made and the materials used. Differing science also has to be used when rolling a bat. A what is good for one, is good for all approach cannot be taken. You have to know exactly how the bat is responding to the amount of pressure being applied, and how much pressure to apply to get it to respond the way you want it to. If you don't, you are just guessing, and you don't want that.
Lets say I am rolling a bat and have applied pressures of 5, 12, and 22 inch lbs' to the bat, and have rotated the bat between the rollers 20 to 25 times at each pressure. From my readings I know the bat has been compressed 200/1000 of an inch (or 1/5) in the process. I have also done this to another bat but it has only compressed 150/1000 of an inch. You can see that the bat that reached 150/1000 of an inch would probably have a thicker barrel construction or be made of a more rigid material. This information tells me that I have to make adjustments to the process if I am going to get the best performance from the bat. I may have to go slower and through more rolling progressions with one bat than the other to attain my objective. Of course the bat rolling techniques I use are much more involved than that but you get the idea.