Products for bench top machinists | LittleMachineShop.com

Collet Block, ER-40 Square

Collet Block, ER-40 Square - Main image
$29.67 $44.95 In stock

A collet block is a precision work holding 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.

  • This collet block provides easy indexing for 2 and 4 divisions.
  • The collet block is 1.75" square and the body is 3.2" long.
  • ER-40 collets have a clamping range of 1/8" to 1" (3.0 mm to 26.0 mm).

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 (4.4 / 5 · 5 reviews)

Benjamin J. ★★★★★

I needed a way to hold my short steel shafts for drilling, and the precision-machined bore in this collet block gripped them without any wobble. The hexagonal shape made it easy to index for repeating operations at 90-degree intervals. It's a simple, well-made tool that does exactly what it should.

Emma ★★★★★

The hex-shaped bore held my brass rod firmly without any wobble during milling. It was a breeze to swap out my round stock for a hex piece thanks to the precise fit. Exactly the kind of solid grip I needed for repeatable work.

Daniel W. ★★★★★

The square body gripped perfectly in my milling vise, and the ER-40 taper held the workpiece dead true with zero wobble. I’ve used cheaper blocks before, but this one’s precision is on another level.