Products for bench top machinists | LittleMachineShop.com

Collet Block, ER-25 Square

Collet Block, ER-25 Square - Main image
$25.97 $39.95 In stock

A collet block is a precision workholding device designed to securely grip and position cylindrical or hexagonal workpieces. Unlike traditional vises that clamp with flat jaws, collet blocks utilize a collet – a slotted sleeve with a tapered outer surface – that collapses uniformly around the workpiece when tightened. This provides a concentric and consistent grip, minimizing the risk of distortion or damage, particularly when working with delicate or thin-walled materials.

  • ER-25 collets have a have a clamping range of 1/16" to 5/8" (1.0 mm to 16.0 mm).
  • This collet block provides easy indexing for 2 and 4 divisions.
  • The collet block is 1.48" square and the body is 2.7" long.

The collet block itself is typically a hardened steel block, often square or hexagonal, with a precision-machined bore to accommodate the collet. The combination of the precision collet and the stable block creates a rigid and accurate platform for a wide range of machining operations.

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.8 / 5 · 5 reviews)

Claire J. ★★★★★

Finally, a collet block that grips my stock without any wobble—the square body sits perfectly in the vise and the ER-25 taper locks down solid every time. I’ve used it for a dozen setups now and it hasn’t let a single hex shaft slip.

Joshua X. ★★★★★

The ER-25 collet block holds my hex stock so snugly that I barely need to torque the wrench to get a chatter-free cut, and the square body sits perfectly flat in the mill vise every time. It's become my go-to for quick setup jobs without any fuss.

Madison K. ★★★★★

The grip on this square block is dead-on repeatable, so swapping hex stock between setups takes no time at all. It’s held up through a dozen jobs without any wobble, and the precision feel is exactly what I’d hoped for.