Our Pick: Sienci LongMill MK2 12x12
It scores 62/100 overall versus 32/100, winning 8 out of 9 comparison categories.
Sienci LongMill MK2 12x12 wins 3 of 4 spec categories. Both are similarly priced. Sienci LongMill MK2 12x12 leads by 30 points overall — here’s where those points come from:
Benchmark Scores
Side-by-side score comparison across all five benchmark dimensions.
Overall
Sienci LongMill MK2 12x12
Pros
- Excellent documentation and beginner-friendly setup from Sienci
- Anti-backlash ACME lead screws on all axes
- gSender is a polished, purpose-built CNC sender
- Active community forums with responsive manufacturer support
- Generous Z-axis travel of 114mm
Cons
- Small 12x12 inch work area for a machine at this price
- Router not included adds $100+ to total cost
- Larger LongMill models offer better value per square inch
- V-wheel motion system rather than linear rails
- Lead screws are slower than ball screws
Snapmaker J1 3-in-1
Pros
- Affordable entry into the Snapmaker ecosystem
- Enclosed design with HEPA filtration for clean indoor use
- IDEX dual-extruder 3D printing is the primary strength
- Compact footprint fits on a desk
- Touchscreen interface is very beginner-friendly
Cons
- CNC module is only 50W -- barely adequate for soft wood engraving
- CNC is an afterthought -- this is primarily a 3D printer
- 320x200mm CNC work area is very small
- Poor value if CNC is the primary use case
- Proprietary modules limit upgrades
Verdict
Sienci LongMill MK2 12x12 wins this comparison with 8 categories to 1.
It scores 62/100 overall versus 32/100, winning 8 out of 9 comparison categories.
Where to Buy
Price-first merchant links with the clearest reason to click first.
Sienci LongMill MK2 12x12
$800Snapmaker J1 3-in-1
$800As an Amazon Associate I earn from qualifying purchases. Affiliate links may earn a commission at no extra cost.
Frequently Asked Questions
What is the difference between Sienci LongMill MK2 12x12 and Snapmaker J1 3-in-1?
The Sienci LongMill MK2 12x12 ($800) features a 710W spindle with a 305×305mm work area and a Steel and aluminum with anti-backlash lead screws frame. The Snapmaker J1 3-in-1 ($800) features a 50W spindle with a 320×200mm work area and a Enclosed aluminum with linear rails frame. Overall, the Sienci LongMill MK2 12x12 wins more comparison categories.
Which is better value for money — Sienci LongMill MK2 12x12 or Snapmaker J1 3-in-1?
Both machines are identically priced at $800. Our value scores rate the Sienci LongMill MK2 12x12 higher at 58/100.
Which router is easier to set up and use?
Based on our ease-of-use benchmarks, the Sienci LongMill MK2 12x12 scores higher (88/100 vs 80/100). Both support gSender, UGS, CNCjs among other software options.