Mini Mill Spindle Box Assembly, R8

Name: Mini Mill Spindle Box Assembly, R8
Brand: Sieg Industrial Group
SKU: 1944
Price: 97.97 USD
Availability: InStock
Rating: 5.0 (5 reviews)

Mini Mill Spindle Box Assembly, R8 - Main image

$97.97 ~~$139.95~~ In stock

This is the spindle box casting for the mini mill, along with all the internal parts. Included are:
An R8 spindle with all the gears, bearings, spacers, and top nut that ride on it.
The intermediate shaft with all the gears, bearings and such that ride on it. This includes the intermediate gear on the top of the shaft.
The high/low speed shifting mechanism.

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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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 (5.0 / 5 · 5 reviews)

Brian ★★★★★ Oct 22, 2026

Installed this on my mini mill last weekend and the R8 spindle runs smooth with zero wobble. The gear engagement was spot-on out of the box, which saved me a lot of fussing.

Evelyn ★★★★★ Oct 21, 2026

The gears and bearings were all pre-installed on the spindle, which saved me a ton of time aligning everything myself. The R8 taper felt smooth and true when I mounted a collet chuck.

Sophia ★★★★★ Oct 20, 2026

Everything I needed for the spindle swap arrived in one box—no hunting for odd spacers or loose bearings. The gears meshed smoothly on first reassembly, and the R8 taper seated cleanly with the drawbar. Definitely saved me from buying piecemeal.