50MM Tooling Arbor Identification

There are three primary types of No. 50 Milling Machine tapered tool holders that Lucas spindles were designed to accept. It is essential to correctly identify the type of tool arbor that you are trying to us in your Lucas so that we can supply the correct Drawback Collet Adapters and Tooling Drive Keys.

Here is a simple method of 50MM Tooling Arbor Identification. Simply use a micrometer and check the distance across the Driving Key 'flats' on the Tooling Arbor you wish to use and compare the dimesion to the information below.

ANSI B5.18-1972 R1991 (Equal depth slots)
Distance across Driving Key Flats: 2.780 / 2.750

REAL ‘Cat-50’ (One Slot 0.100 Shallow)
Distance across Driving Key Flats: 2.875 / 2.865

ANSI B5.50-1978 (One Slot 0.200 Shallow)
Distance across Driving Key Flats: 2.989 / 2.95