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Chuck Adapter, M39 x 4 Thread 4" Diameter 

Chuck Adapter, M39 x 4 Thread 4" Diameter
  • 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
Part Number: 1921
Weight: 2.40 lb

Price: $34.95

In stock
Quantity:
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 Chris' Tips
Too many adapters? See our chart that correlates lathe spindle threads to lathe chuck adapters and our 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.

We provide complete instructions for mounting the adapter. Our transfer screw sets are the perfect tool for marking the chuck mounting holes on a lathe chuck adapter.

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 3.9" (100 mm)
Thread M39x4
Bolt Holes None
Hub Diameter Ø 2.2" (56 mm)
Hub Length Ø 0.9" (24 mm)
Flange Thickness Ø 0.6" (16 mm)
Registration Boss Ø 0.1" (3 mm)
Registration Diameter Ø 2.8" (72 mm)

Compatibility

This product works with these LittleMachineShop.com products:

This product works with lathes with a M39x4 chuck mount including:

  •   Grizzly G4000 9x19 Bench Lathe
  •   Harbor Freight 45861 Central Machinery 9x20 Bench Lathe