Big Kaiser’s RBX12 air-drive spindle achieves variable rotational speed of 100,000 to 120,000 rpm and enables existing machines to be upgraded for high-speed micromachining. Big Kaiser’s RBX12 air-drive spindle achieves variable rotational speed of 100,000 to 120,000 rpm and enables existing machines to be upgraded for high-speed micromachining. This is possible because the spindle is driven by air supplied through a stop block or through the machine spindle. Operating at such high speeds helps to improve machining accuracy, enhance surface finish, lengthen tool life and reduce processing time as well as wear on the cutting tool, the company says. The spindle’s ceramic ball bearings and precise collet system provide high runout accuracy, which enables ultra-thin wall cutting. The AA-grade Mega Micro Collet provides 1-micron runout at the collet nose, and 0.004" collapsibility provides near-perfect concentric clamping of a micro-tool shank. The RBX12 also minimizes thermal displacement to less than 0.001 mm in the Z axis for maximum precision. This spindle is available with BCV40, BBT30/40 and HSK-A63/F63/E32 interfaces. Models not requiring a stop block have a body diameter of 1.260" (32 mm). Options for automatic tool changing are also available.