Image: Sienci Labs
Sienci Labs AltMill MK2 4x4
Sienci Labs
Best for: The serious hobbyist or small shop stepping up from a belt machine who wants industrial motion components without industrial pricing
Typical starting price
$4,290Editorial baseline for this machine
Overall score
Best current buying path
Where to buy
Prices change often: compare the stores below
- Shipping varies by retailer
- Check manufacturer site for availability
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Quick verdict
The AltMill MK2 4x4 combines HGR15 linear guides, ball screws and closed-loop steppers with an SLB-EXT grblHAL controller and free gSender software. Its current resource table lists a 1265 x 1251 x 174 mm cutting area. The machine includes its metal legs, while the spindle, wasteboard, tooling, workholding and extraction need separate provision. Manual spindle and automatic-tool-change packages have different costs and requirements. Compare complete configurations rather than treating the machine-only price as ready-to-cut, and check current lead time and regional availability.
Who this fits best
The serious hobbyist or small shop stepping up from a belt machine who wants industrial motion components without industrial pricing
Buy this if
The serious hobbyist or small shop stepping up from a belt machine who wants industrial motion components without industrial pricing. HGR15 linear guides and ball screws on all three axes.
Skip this if
Spindle packages cost extra; automatic tool changing adds substantially more than a manual spindle kit, and heavy, and assembly is a real project.
What else you still need
A spindle package, computer, wasteboard, tooling, workholding and dust collection. Metal legs are included; assembly and setup are still required.
Material reality check
Wood, sheet goods, plastics and aluminum with appropriate tooling and cutting parameters across a 4 x 4 class bed.
Better alternative if...
you prefer the smaller PRONAX platform with its compatible NAX5 automatic tool changer; compare complete ATC bundles. See Genmitsu PRONAX Forge
Where it wins
- HGR15 linear guides and ball screws on all three axes
- Closed-loop steppers with auto-correction catch lost steps
- gSender is free, actively developed, and genuinely good
- Optional 2.2kW ATC spindle puts automatic tool changing within reach
- Made in Canada with a strong documentation and support culture
Where it falls short
- Spindle packages cost extra; automatic tool changing adds substantially more than a manual spindle kit
- Heavy, and assembly is a real project
- Maker currently quotes one week lead time; check destination availability
- Setup includes the grblHAL controller, gSender and the chosen spindle package
- Machine-only pricing makes direct comparison with all-in machines misleading
Specifications
1265 × 1251 mm
15825 cm²
2200W
80 mm mount only; optional 1.5 kW, 2.2 kW or 2.2 kW ATC spindle packages
SLB-EXT running grblHAL, with closed-loop steppers and auto-correction
n/a
$4,290
premium
Full specification table
Relative to database
Benchmark Scores
Overall Score
Composite across 5 dimensions
Community Sentiment
We have not summarised owner feedback for the Sienci Labs AltMill MK2 4x4 yet, so this section is intentionally left without claims. Check the sources for current owner discussions.
Community sentiment is aggregated from forums, Reddit, Discord, and manufacturer communities. Individual experiences may vary.