Sienci Labs · Open-frame router · New
AltMill MK2
Sienci’s big, fast ball-screw machine — 2×4 or 4×4, 174 mm of Z, and a real path to an automatic tool changer.
$2,7902×4, no spindle. 4×4 is $3,160.
Work area1265 × 635 mm
SpindleBring your own
DriveBall screw
MetalAluminum, comfortably
Will's take
The best price-to-capability ratio in the big-router class right now.
The AltMill MK2 is the Shapeoko 5 Pro’s biggest rival and, on paper, it wins on value: ball screws and HGR15 rails everywhere, 600+ IPM rapids, the deepest Z in this group, and an optional ATC spindle that very few hobby machines offer.
You’ll need to add a spindle and a stand, and it’s big — this is not a benchtop machine in any real sense. Sienci also ships in batches, so plan around lead times. But if you have the space and want to grow into production work, I’d shortlist it.
— Will
What I like
- Ball screws and rails on all axes
- Deepest Z here (174 mm)
- Optional ATC — rare at this price
- Open grblHAL ecosystem
What I'd watch for
- Spindle and stand are extra
- Large and heavy
- Batch shipping and lead times
Spec sheet Sienci Labs AltMill MK2
| Work area (X × Y × Z) | 1265 × 635 × 174 mm 49.8 × 25.0 × 6.9 in |
|---|---|
| Spindle | Bring your own — 2.2 kW VFD kit optional |
| Drive | Ball screw |
| Linear motion | HGR15 linear rails |
| Frame | Machined aluminum extrusion |
| Enclosure | No |
| Tool changer | Optional ATC spindle kit |
|---|---|
| Controller | SLB-EXT (grblHAL) |
| Software | gSender (free) |
| Metal | Aluminum, comfortably |
| Footprint | 63 × 38 in (2×4) |
| Released | 2025 |
Still confirming with Sienci Labs: price (from US reseller listing).
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