Products for bench top machinists | LittleMachineShop.com

Chuck Adapter, Unthreaded 4" Diameter

Chuck Adapter, Unthreaded 4" Diameter - Main image
$27.17 $39.95 In stock

Cast iron lathe chuck adapter can be threaded to fit any spindle nose thread. It has a 3/8" smooth pilot hole. This adapter is 4" (100 mm) in diameter and has no chuck mounting holes. Use it for all 3" and 4" chucks.

* 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.

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Customer Reviews (4.8 / 5 · 5 reviews)

Richard ★★★★★

Machined the threads on my lathe to match my spindle nose and the cast iron took them perfectly—no chatter at all. The 3/8" pilot hole was dead-on for centering, so I didn't have to fight any wobble. Exactly what I needed for a custom chuck setup.

Stella ★★★★★

The 4-inch diameter gives me plenty of room to work on larger pieces without swapping chucks. That 3/8" pilot hole kept everything perfectly centered while I drilled my own mounting pattern. Solid cast iron, no wobble at all once it's snugged down.

Abigail ★★★★★

The unthreaded design made it easy to add my own threads for a precise fit on my lathe. That 3/8" pilot hole was exactly the right size for centering my workpiece. Solid cast iron feels heavy and durable.