About Sherline’s 3C Collet Spindle Headstock
Our 3C Collet Headstock came from customers’ requests. Many customers asked for a spindle and collet to allow larger diameter stock to go through the headstock. With the 3C collet, our customers can now hold stock up to 1/2″ diameter that will pass through the headstock.
The 3C Collet Headstock is interchangeable with our standard headstock. The centerline height is the same, and the mounting system is the same. Therefore you can easily switch from our other headstocks to the 3C headstock.
The 3C Spindle is electroless nickel plated to aid in rust prevention and increase the spindle’s surface hardness for durability. The headstock includes a spindle pulley and a precision ground head key.
If you wish to use a chuck with the 3C headstock, you can purchase the 3C to ¾-16 chuck arbor. All of our 3- and 4-jaw chucks with a ¾-16 thread will fit on this arbor.
When it comes to making the 3C collets, we can’t compete with the cheap import collets, and companies like Hardinge already make quality 3C collets in many sizes. Therefore, we leave it up to you to decide from whom you want to buy your collets.
3C Collet Range Specifications
| Inch | Metric |
|---|---|
| .070″ – .542″ | 1 mm – 13 mm |
NOTE: Hardinge also offers custom sizes and both hex and square sizes.
NOTE: Certain attachments, like the Thread Cutting Attachment, the Lathe Power Feed, and the 10,000 RPM Pulley Set, will NOT work with the 3C Collet Headstock. If you are uncertain if an accessory will work with the 3C Collet Headstock, please contact us for more information.
- Class 3 or Class 5 Bearings
- With or without a DC Motor and Speed Control Unit
NOTE: The 3C collet spindle has standard electroless nickel plating. There is NO option for a plain finish.
Bearing Options
The bearings in the headstocks are offered in two classes: C3 and C5.
The C3 bearings have been standard in all of our headstocks for years and have proven reliable over that time.
The C5 bearing headstocks come at a higher price than the standard C3 bearings headstocks, but they run smoother, quieter, and cooler than our regular class 3 bearing headstocks and are more suitable in an industrial setting.
Sherline’s new C5 headstocks feature two 20 mm, class 5, lifetime-lubricated ball bearings with an adjustable preload nut. The preload is adjusted at the factory to .0002″ (.005 mm) of endplay. The preload adjustment is controlled by the outer races of the bearings being held apart by the headstock case and the inner races being pulled together by the preload nut. This is appropriate for extended running at speeds of 4000 RPM or less. You may need a slightly looser preload setting of .0003″ for operating speeds up to 10,000 RPM.
Optional DC Motor with Speed Control
You can order your headstock with or without our DC motor and speed control unit.
The powerful DC motor offers its maximum torque at low RPM, where you need it most in machining. This means it provides far more useable power than an AC/DC motor of equivalent or larger size. It also offers smoother and quieter operations than an AC/DC motor.
A sophisticated speed control unit powers and controls the motor. The speed control unit accepts any incoming AC current from 100 VAC to 240 VAC, 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 entire range’s speed. 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*.
*NOTE: The full torque at the lower RPM range of 70-1,400 will be obtained when the motor pulley belt is in the low-speed/high-torque pulley groove. The high-speed pulley groove will have full torque in the 1,200 to 2,800 RPM range.
