Sienci Labs AltMill MK2 2x4 vs Sienci Labs LongMill MK3 30x30
Two desktop CNC routers side by side, from each maker's own page, read 1 November 2026. Neither has been tested for this site, so this shows what each maker publishes, not which cuts better.
Where they differ
- Sienci Labs LongMill MK3 30x30 is listed $2,490 lower ($1,400.00* against $3,890.00*).
- Sienci Labs AltMill MK2 2x4 has the larger published X × Y work area: 1245 × 635 mm against 813 × 813 mm (1.2× the area).
- Sienci Labs AltMill MK2 2x4 lists more Z: 140 mm against 117 mm.
- Drive: Sienci Labs AltMill MK2 2x4 has ballscrew drive; Sienci Labs LongMill MK3 30x30 has leadscrew drive.
- Published footprints: 1,499 × 965 mm against 1,016 × 1,143 mm.
- Ready to cut (machine plus the cheapest sourced router or spindle, before bits): $4,815 against $1,565.
Published specs
| Sienci Labs AltMill MK2 2x4 | Sienci Labs LongMill MK3 30x30 | |
|---|---|---|
| Price | $3,890.00* | $1,400.00* |
| Work area | 1245 × 635 mm | 813 × 813 mm |
| Z | 140 mm (5.5") | 117 mm (4.6") |
| Spindle or router | Not included; standard 80 mm spindle mount. Optional 1.5 kW and 2.2 kW ER20 spindle kits and a 2.2 kW ATC kit. | Not included ("Router and other accessories sold separately") |
| Drive | Ballscrews on all axes | T12 leadscrews, all axes |
| Linear guides | HGR15 linear guides on all axes | 15 mm profiled linear guide rails, all axes |
| Controller and motors | SLB-EXT controller with e-stop. Closed-loop steppers on all three axes; about 600 in/min. | SLB-LITE controller, grblHAL. Closed-loop NEMA 23, 1.2 Nm. |
| Software | Not published | gSender (sender); page says most buyers use Vectric VCarve Pro or Carveco |
| Footprint | 59″ wide × 38″ deep | About 40" x 45" x 20" (1016 x 1143 x 508 mm) |
| Weight | 76 lb | About 72 lb assembled (see disagreement) |
| Warranty | 365 days from receipt | 365 days from receipt (policy effective 1 Aug 2026) |
| Spec notes | None found | 1 |
| Source | Maker’s page ↗ | Maker’s page ↗ |
Work areas to scale
Open in the compare tool See them on your bench
Why this pair
Pairs are picked by a rule: machines in the same size class and within about 60% of each other's price, plus each machine's nearest sibling from the same maker. No search or keyword data was used. All 46 pairs.