Sienci LongMill MK3 48x30
#4 in LargeFull review
For a hobbyist who wants a rigid rail machine with a 49 by 32 inch bed for well under $2,000, and already has or will buy a trim router.
Sienci Labs $1,800$1,800
The Sienci LongMill MK3 48x30 is the better CNC router overall, rated 3.5 to 3.3. The Sienci LongMill MK3 48x30 leads on price and motion. The Carbide 3D Shapeoko 5.1 Pro 4x4 wins on work area and warranty. The Sienci LongMill MK3 48x30 costs $2,000 less ($1,800 vs $3,800).
Carbide 3D Shapeoko 5.1 Pro 4x4
#6 in LargeFull review
For a small shop that wants rails and ballscrews on a 4x4 bed with US support. Add the cost of a router before comparing it with machines that include one.
Carbide 3D $3,800$3,800
Prices were last checked November 2, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the Sienci LongMill MK3 48x30 for price ($1,800 vs $3,800) and motion (linear rails, screw or rack drive, limit switches, closed-loop steppers vs linear rails, screw or rack drive, limit switches).
- Choose the Carbide 3D Shapeoko 5.1 Pro 4x4 for work area (2,372 sq in (48.7 x 48.7 in) vs 1,568 sq in (49 x 32 in)) and warranty (1.5-year warranty vs 1-year warranty).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every large CNC router; a clear win is highlighted. How we rank explains each one.
| Factor weight | Sienci LongMill MK3 48x30 | Carbide 3D Shapeoko 5.1 Pro 4x4 |
|---|---|---|
| Overall rating | 3.5/5 | 3.3/5 |
| Price 25% | 85 $1,800 | 23 $3,800 |
| Work area 15% | 48 1,568 sq in (49 x 32 in) | 100 2,372 sq in (48.7 x 48.7 in) |
| Spindle 15% | 50 spindle power not published (neutral score used) | 50 spindle power not published (neutral score used) |
| Motion 20% | 100 linear rails, screw or rack drive, limit switches, closed-loop steppers | 85 linear rails, screw or rack drive, limit switches |
| Warranty 25% | 0 1-year warranty | 25 1.5-year warranty |
Specifications
| Sienci LongMill MK3 48x30 | Carbide 3D Shapeoko 5.1 Pro 4x4 | |
|---|---|---|
| Work area | ||
| Travel (X x Y x Z) | 49 x 32 x 5.1 in | 48.7 x 48.7 x 6.1 in |
| Area | 1,568 sq in | 2,372 sq in |
| Spindle | ||
| Spindle | 65 mm router or 80 mm spindle mount (router not included) | 65 mm trim router mount (router not included) |
| Motion and control | ||
| Frame | - | custom extrusions on a rigid base frame |
| Linear rails | Yes | Yes |
| Drive | Lead screw | Ball screw |
| Closed-loop steppers | Yes | - |
| Limit switches | Yes | Yes |
| Controller | SLB-LITE with grblHAL | Carbide Motion |
| Offline controller | - | No |
| Build | ||
| Weight | 80 lb | - |
| Warranty | 1 year | 1.5 years |
| Released | 2026-09 | 2025-11 |