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Chuck Adapter, M39 x 4 Thread 4" Diameter

Chuck Adapter, M39 x 4 Thread 4" Diameter

SKU:1921

Regular price $39.95 USD
Regular price Sale price $39.95 USD
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Key Features

  • Cast iron lathe chuck backplate adapter fits lathes with M39 x 4 spindle nose thread
  • Adapter is 4" (100 mm) in diameter and has no chuck mounting holes
  • For all 3" chucks and 4" chucks
  • Includes instructions for final turning of the registration diameter to ensure concentricity

WARNING: This product can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.

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Product Information

Description

This chuck adapter fits 9x20 lathes that have a M39x4 spindle nose thread.
Use this adapter to mount 4" chucks such as LittleMachineShop.com PN 1698 4" 3-Jaw chuck or PN 1588 4" 4-Jaw chuck.
There are no holes in this adapter so you can drill it for either a 3-jaw or 4-jaw chuck.
*NOTE* These adapters require machining on the lathe on which they will be used.
Instructions are included for final turning of the registration diameter on your lathe to ensure perfect concentricity.

Chris's Tips

Too many adapters?

See our chart that correlates lathe spindle threads to lathe chuck adapters 

Here is a chart that provides dimensions of threaded lathe chuck adapters.

These adapters must be machined on your lathe to fit the chuck so that it is concentric on the lathe. In most cases you have to drill the chuck mounting holes also.


WOODWORKERS: Our threaded adapters are not suitable for use on wood turning lathes. Please do not purchase them for this application. These adapters require machining on the lathe on which they will be used, and this is impossible on a wood lathe.

Specifications

Nominal Size: 4"

Outside Diameter: Ø 3.937",100 mm

Thread: M39x4

Bolt Holes: None

Hub Diameter: Ø 2.205", 56 mm

Hub Length: Ø 0.945", 24 mm

Flange Thickness: Ø 0.630", 16 mm

Registration Boss: Ø 0.118", 3 mm

Registration Diameter: Ø 2.835", 72 mm

Product Instructions