Model 3R BLOCK-HEAD®

The model 3R BLOCK-HEAD® air bearing fits well in high-speed applications like dicing saws or I.D. grinders. Its sub-millionth-inch accuracy and high central stiffness enable controlled material removal even in tough or brittle materials. Specifications (at 150 psi) Load Capacity Ultimate Working Radial 65 lb 32 lb Axial 170 lb 85 lb Tilt 140 in-lb 70 in-lb Stiffness Radial 0.5 lb/microinch Axial 1.5 lb/microinch Tilt 1.6 lb-in/microradian Error Motion Radial < 1 microinch Axial < 1 microinch Tilt < 0.1 microradian Total Weight 7.25 lb Rotor Weight 3.2 lb Rotor Inertia 0.16 oz-in-sec2 Maximum Speed 15,000 rpm Air Consumption < 2 scfm Metric Specifications

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Load capacity and stiffness are approximately linear with air pressure.

Ultimate load capacity is measured when metal-to-metal contact is made across the bearing surfaces. Working load capacity is half of the ultimate load capacity. Rotor weight must be included as part of total spindle load.

Axial and tilt loads are supported by the same bearing surfaces. Consequently, a load applied in one mode reduces the other mode proportionally.

High speed or high inertia applications require rotor containment. Maximum speed is dependent on application. Consult Professional Instruments for further information with regard to speed.