An R8 Collet is a precision tool-holding collet designed for R8 spindle milling machines, commonly used on Bridgeport-type mills. It provides accurate centering, strong gripping force, and quick tool changes for holding end mills, drills, and cutters.
An R8 Collet is a tool-holding collet designed for R8 spindle milling machines (commonly Bridgeport-type mills).
It provides accurate centering, strong grip, and quick tool changes for end mills, drills, and cutters.
KEY FEATURES
R8 COLLET – STANDARD DIMENSIONS
| Parameter | Dimension |
| Collet Type | R8 |
| Taper | R8 Taper (7/24) |
| Major Diameter | 31.75 mm (1.25") |
| Overall Length | ~101.6 mm (4") |
| Drawbar Thread | 7/16" – 20 UNC |
| Keyway Width | 4.76 mm (3/16") |
| Typical Accuracy (TIR) | ≤ 0.010 – 0.02 mm |
R8 collets are single-size collets (each collet holds one exact size).
R8 COLLET – COMMON HOLDING SIZES
Inch Sizes
Metric Sizes
CONSTRUCTION DETAILS
TYPES OF R8 COLLETS
APPLICATIONS
SUPPLY OPTIONS
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