Sherline 9/16 Inch Headstock and Motor Unit 3309
9/16 Inch Through Hole Spindle
Internal through hole opened up to a maximum of 9/16″. Please note that while this allows larger stock to pass through the headstock, it also eliminates the #1 Morse internal taper, meaning tapered tools like drill chucks, fly cutters, etc. cannot be held in the headstock. It is also not compatible with the thread cutting attachment or lever collet closer.
Threaded tools can still be used such as 3/4 jaw chucks and end mill holders.
To power, and control the motor a more sophisticated speed control unit is required. This unit accepts any incoming AC current from 100V AC to 240V AC, 50 or 60 Hz and automatically outputs 90V DC to the motor so that this unit can be used anywhere in the world without a transformer. All you need is the correct wall plug or converter. Once the on/off switch is switched to the “ON” position, a speed control knob is used to vary the speed over the entire range. With the pulley in the “normal” position, the speed range is about 70 to 2800 RPM. In the “high torque” position the maximum speed is cut in half, but torque at any given speed is much greater.
This unit can be purchased to replace an existing AC/DC motor on an older Sherline machine, to turn a mill XYZ base into a complete mill so that you don’t have to swap power units back and forth from the lathe, or as a stand-alone unit for custom tooling designs. This very compact and well-engineered unit costs far less than other DC units of similar power offered in major industrial tool supply catalogs.