The J-Slot: Mosaic Tile Production

The facility we visited was really impressive.  They process thousands of porcelain tiles a day into custom mosaic sheets running several of these multi-blade machines. This workhorse is fitted with fourteen 12” J-Slot blades.


The machine is fed large format porcelain tiles that get cut into strips or varying sizes depending on the customer’s specifications.  For smaller mosaic pieces, the strips are fed back into the machine to be cut down a second time. 


What was most impressive was the speed with which this machine could process this notoriously hard material.  Porcelain rates between a 6.0 and 7.0 on the Mohs scale of mineral hardness.  So what makes this J-Slot blade so well suited for cutting porcelain?  We sat down with Vincent to get the details.


He began by first explaining the anatomy of the J-Slot segment. The segment is 1.6mm thick, which is quite thin by sintered segment standards. A thin segment has less resistance. Less resistance, means faster cutting. Cutting at high speeds requires a quality diamond segment. But, let’s be honest, there are a few blades on the market that can claim these same advantages. It’s what he explains next that really captured our attention.


Typically processing facilities, such as the one we visited, would use continuous rim blades to cut porcelain. As the blades run continuously on these machines, tension builds up in the steel core due to the cutting resistance and centrifugal force. Vincent explains that the continuous sintered rim of these blades act like a rigid ring around the perimeter of the blade preventing the core from being able to dissipate the tension. Unable to release this force, the blade fails, the body warps and no matter how great the segment, the blade is rendered worthless.

The segments of the porcelain J-Slot blade are specifically designed to have narrow spaces in between each segment. Below these small gaps is a razor thin j-slot in the steel core. The j-slot, coupled with thin gaps between the segments allows the tension of the blade to dissipate. By releasing the tension on the core, the integrity of blade is maintained.


Vincent explains that blade tension is one of the least understood concepts of cutting blades. While most people are concerned about the segment attributes, he explains that the steel core is by far the most important component. The core can be weakest point on any blade and understanding tension, especially on continuously running machines is critical. He’s worked closely with this facility to fit their machines with the right blade for the job and the result is a high-end product, but more importantly, a satisfied customer.