ER-16 Headstock

ER-16 collet nut included.

SKU: 30111 Category:

Product Description

For use on a Sherline lathe or mill in place of the standard headstock if you are wanting an ER-16 spindle.

Keep in mind that if the ER-16 nose is ordered, no Sherline accessories that use a #1 Morse taper or 3/4-16 thread will work on this spindle.

The ER-16 nut that ships with your order may be plain or have a black oxide finish.

NOTE: We do not sell the collets used with the ER-16 spindle. Those are available through MSC Industrial Supply Co. or other tool supply sources.

ER-16 Collet Range Specifications

Inch Metric
.020″ – .393″ .5 mm – 13 mm

Optional ER-16 Collet Nut Spanner Set

We offer an ER-16 collet nut spanner set for the ER-16 headstocks. The spanner set includes two wrenches: One has a pin that engages one of the holes in the Sherline spindle to keep it from turning while the nut is tightened, and the other is a hex wrench sized to fit the special ER-16 nut (the spanner set is not included with the headstock).

Headstock spindle bore .406″
Headstock spindle nose internal taper 16° taper
Headstock spindle external thread 22 x 1.5 mm
Pulley groove side angle 19°
Spindle Runout (at spindle nose), Maximum allowable (Most are within .0005″) 0.001″
Spindle End Play (adjustable with preload nut), Factory Settings with 2800 RPM Pulleys: 0.0002″with 10,000 RPM Pulleys: 0.0003″
Designation/stock number (ZZ refers to “double shielded”) 6004ZZ
Size of bore 20 mm (0.7874″)
Tolerance of bore 0.0004″
Outside Diameter 42 mm (1.6535″)
Tolerance of OD 0.0005″
Width 12 mm (0.4724″)
Bearings 9 balls, 1/4″ Dia.
Headstock Bearing Replacement

We don’t recommend that customers replace the headstock bearings. We use custom fixtures to align the spindle and the bearings. You must return your headstock to our facility for bearing replacement*. Contact our customer service department,, for an RMA number before sending your headstock back for service.
*NOTE: Fees apply
Click the links below to learn more about the specialized fixtures and procedures for setting the headstock bearing preload.
PDF: Replacing Headstock Bearings
Video: Setting the Headstock Bearing Preload

31080 10-32 X 3/8″ Set Screw
40100 Headstock Casing
40160 Preload Nut
65026 ER-16 Collet Nut
65023 ER-16 Headstock Spindle
40320 Bearing Washer (SS)
40330 10-32 X 5/8″ Skt Hd Cap Screw (2)
40420 Headstock Bearing (2)
40440 #2 X 1/4″ Pan Hd Sheet Metal Screw (2)
40520 10-32 X 3/16 Cup Pt Set Screw
40540 5/16-18 X 3/4″ Cone Point Set Screw
40540 5/16-18 X 3/4″ Cone Point Set Screw
43230 Stepped Main Spindle Pulley

Click the P/Ns below to download a zipped version of the IGS 3D CAD files. You will need to extract the zip file before viewing the IGS file.
30111 ER-16 Headstock 3D IGS Model
65026 ER-16 Collet Nut 3D IGS Model
You need an IGS viewer to view .igs files. CLICK HERE to download a FREE IGS viewer.