I usually purchased the end mill of the TiAlN coat of the monotaro brand, but I purchased the product because there was no blade diameter of 5.5 mm. Soon the blade spilled and ramped up on the workpiece, the hardships took place in the water bubbles. I will not buy it again.
It is key groove processing with a drilling machine, but the optimum rotation number is well understood I tried it properly but is it feel like it is not possible and not possible? I can use it well enough.