One of the issues in Bat Rolling is what is known of in the industry as bat slippage. I have not seen this problem discussed in any articles that I have read. I am going to tackle this issue in the article and educate and enlighten you to the problem as well as the solutions.
There are basically two styles of Bat Rolling Machines on the market. They are know as Perpendicular and Parallel Bat Rolling Machines.
In a perpendicular machine, bat slippage is not as big of an issue as you are only compressing a very small area of the composite bat at a time. In a parallel machine this problem can show up. For the most part it appears when you are trying to roll stiffer bats or the newer bats that have more laminate glues being used.
In a parallel machine you have a greater area of the bat being compressed at a time. For this reason slippage can show up on certain parallel bat rolling machines.
It would seem that an easy solution would be to only use a perpendicular machine, however they are antiquated and limited to there ability to fully roll a bat to its’ maximum potential.
Most parallel machines will also roll perpendicular, so it is an obvious conclusion that they are a superior machine. Since the lion share of all machines on the market today are parallel machines, I will not expound on this area.
The plastic being used in the rollers are the main area of discussion on this topic. A simplified explanation of the slippage is that the plastics being used are very slick, and the bats being rolled are also very slick. The natural result is slippage at higher compression levels of the bat rolling process.
Other areas can come into play, such as the bearings being used and alignment, etc. However the number one reason for this problem area is slippage.
Too hard of plastics that are also slick is one problem area. One plastic that is used today is a plastic called Acetal, the trade name for this plastic is Delrin. This plastic is very slick and also very hard. The hardness does not allow this plastic to have much of a footprint on the bat during the rolling process, thus it has less surface area to grip. With the hardness and slickness of this material, slippage is often the end result when rolling at the higher levels of compression.
Another plastic being used in most machines is a high density plastic that is also very slick, but does have a have more surface area on the bat when rolling. It is a better solution but still has slippage problems at the higher levels of compression. Adding texture to this plastic during the machining of the rollers helps to eliminate this problem.
One Plastic Solves the Slippage Problem:
There is now a third material that is being listed as a proprietary plastic that eliminates this problem all together. The reason being that it is not nearly as slick and grips the bats really well, thus eliminating the problem. It also is softer then the Acetal plastic, so it has a better footprint on the bat. This plastic used in these Bat Rolling Machines is expensive, so you are only seeing it on some of the higher end machines on the market.
The slippage problem of bat rolling is know in the industry but seldom discussed. Some of the high end machines are solving this problem by using expensive, but effective plastics in them. The best solution for the consumer is to gain knowledge in this area and simply ask the manufacturer and or sales representative what there is available that eliminates this situation.