CAIBI EQUIPMENT ASSESSMENTSienci Labs

AltMill MK2 2×4

Large 2×4 CNC router with linear rails, ball screws and closed-loop steppers aimed at production-capable woodworking and light metal work.

CAIBI · PROVISIONALA strong large-format value proposition, but it should be compared on installed-system cost rather than machine-only price. It competes more naturally with Shapeoko/Onefinity than with compact enclosed Makera machines.

REVIEW EVIDENCE

Still provisional

The owner evidence is useful but not sufficiently independent/editorial for CAIBI to call this a final reviewed consensus yet.

Read the source evidence

Sienci verified owners

Verified owner feedback is strongly positive overall on rigidity, value and support, but also contains examples of alarms, failed parts and stand flex.

Read source ↗Sienci Community Forum

Owner discussion shows a split between highly capable machines and frustrating QC/setup cases, with support generally helpful but sometimes slow.

Read source ↗Sienci Community Forum

Recent owners repeatedly praise accuracy, openness and support, while acknowledging occasional component issues.

Read source ↗

WHERE TO BUY

Current buying routes

These are the regional prices and bundles CAIBI last checked. Always confirm the live price before buying.

UKNo checked route yet

No current direct GBP AltMill 2 x 4 route was verified. Sienci is Canadian and can show CA$3,890 on Canadian store surfaces; do not treat that as USD or convert it into a UK retail claim.

US1 checked route

manufacturerSienci Labs

$2,790 USD machine only

Sienci’s current AltMill comparison page states the 2 x 4 price as $2,790 USD and identifies the figures as August 2026 prices.

The machine ships with an 80mm spindle mount but the spindle is sold separately. Current spindle/dust-shoe kits add materially to the usable setup total.

Checked 5 Sep 2026 ↗

The current manufacturer comparison explicitly states $2,790 USD machine only, with spindle sold separately.

REQUIRED EXTRAS1.5kW/2.2kW spindle or supported ATC spindle routeCutting toolsWorkholdingDust collection

ONGOING CONSUMABLESEnd mills/cuttersSpoilboard and workholding material

WHAT IT UNLOCKS

Capabilities

25 × 49 in working area
Closed-loop steppers
Ball screws and HGR15 linear guides
600+ IPM class motion
Hardwoods, plastics, composites and light metal capability
Support for 80 mm spindles and ATC options

LIMITS

What to know before buying

Spindle is not included in base machine
Large 59 × 38 in footprint
Dust collection and spoilboard are extra
Owner evidence shows some QC and support-resolution variability
Regional compliance and power configuration need checking outside North America

SOURCE

Key manufacturer specifications

Work area: 25 × 49 in
Z height: 5.5 in max
Motion: Closed-loop steppers + ball screws
Footprint: 59 × 38 in
Spindle mount: 80 mm; spindle sold separately

SOURCE TRAIL

Specifications, documentation and pricing

manufacturerSienci AltMill MK2 2×4↗

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