Jerry's Original High Speed Auxiliary Mill Spindle

An easy to make auxiliary high speed spindle that will allow you to utilize very small diameter end mills without a high probability of breakage. Spindle RPM's of most home shop milling machines are simply too slow for end mills smaller than around 1/16" (1.6mm). Depending on the motor used and the pulley ratio, speeds of 8,000 RPM and much higher are available. The spindle is designed to accept 3/16" shank diameter end mills which is common for end mills from 1/32" to 3/16" diameter. The spindle body is mounted in a standard 3/4" or 7/8" R-8 cullet. The drive belt is a standard low cost "O" ring. The unit is adaptable to a wide range of modifications to suit any user. The plans set also includes an oversize computer grade precision lower ball bearing, a high quality upper ball bearing and a bearing preload wave washer.