Products for bench top machinists | LittleMachineShop.com

Collet Chuck, ER-20, R8, Professional Grade

Collet Chuck, ER-20, R8, Professional Grade - Main image
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$73.67 $109.95 In stock

R8 to ER-20 professional grade collet chuck. Premium 20CrMnTi alloy steel hardened and all ground body for extended tool life.
The maximum RPM is 8,000 and the maximum runout is 0.0002" (0.0058 mm). The R8 drawbar thread is 7/16"-20.
ER-20 collets have a range of 1/16" to 1/2" (1.0 mm to 13.0 mm).
*Collet must be assembled into a collet chuck nut before inserting into the collet chuck.

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Customer Reviews (5.0 / 5 · 5 reviews)

David U. ★★★★★

The hardened alloy steel body really locks in my end mills without any noticeable runout—measured it at just under 0.0002" on my indicator. Perfect for finishing work on my mill.

Mia ★★★★★

Swapped out the old chuck for this ER-20 R8 and the runout is barely measurable at 0.0002", which made a huge difference in my routing precision. The hardened steel body feels significantly more solid than the last one I used.

Lucy ★★★★★

Finally, a collet chuck that holds my end mills without any noticeable wobble; the 0.0002" runout is no joke. I've been pushing it to 8,000 RPM and the ground body stays true even after several heavy cuts.