Machine Comparison
Mitsui Seiki H6D vs Mitsui Seiki J6CN
Mitsui Seiki vs Mitsui Seiki · CNC Boring Machines
Summary
The Mitsui Seiki H6D and Mitsui Seiki J6CN are both from Mitsui Seiki's cnc boring machines lineup, making this a common upgrade or lineup decision for shops already invested in the Mitsui Seiki ecosystem. The Mitsui Seiki H6D leads in rapid traverse (15 m/min (591 ipm) vs 10 m/min (394 ipm)). The Mitsui Seiki H6D leads in tool capacity (30 tools vs 20 tools). These machines are closely matched across most specifications, making the decision more about specific feature priorities, dealer support, and your existing shop ecosystem than raw spec advantages. Both machines are proven performers in production environments and represent solid investments for shops in the market for a cnc boring machine.
Specifications Comparison
| Specification | Mitsui Seiki H6D | Mitsui Seiki J6CN |
|---|---|---|
| X-Axis Travel | 600 mm (23.6 in) | 600 mm (23.6 in) |
| Y-Axis Travel | 700 mm (27.6 in) ▲ | 500 mm (19.7 in) |
| Z-Axis Travel | 500 mm (19.7 in) ▲ | 400 mm (15.7 in) |
| Tool Capacity | 30 tools ▲ | 20 tools |
| Rapid Traverse | 15 m/min (591 ipm) ▲ | 10 m/min (394 ipm) |
| Table Size | 630 x 500 mm (24.8 x 19.7 in) | 800 x 500 mm (31.5 x 19.7 in) ▲ |
| Accuracy | +/-2.0 um | +/-1.0 um ▲ |
| Repeatability | +/-1.0 um | +/-0.5 um ▲ |
| Control | Fanuc 31i-B | Fanuc 31i-B with high-resolution scales |
| Max Table Load | 800 kg (1,764 lb) | 800 kg (1,764 lb) |
| Spindle Speed | 6,000 rpm | 8,000 rpm ▲ |
| Spindle Taper | BT50 | BT40 |
| Spindle Motor | 15 kW (20 HP) continuous ▲ | 7.5 kW (10 HP) continuous |
| Scale Resolution | 0.1 um ▲ | 0.01 um (10 nanometers) |
| Price Range | $400,000 - $600,000 | $400,000 - $550,000 |
Advantages
Mitsui Seiki H6D
- Greater y travel of 700 mm (27.6 in) accommodates larger workpieces
- Greater z travel of 500 mm (19.7 in) accommodates larger workpieces
- Larger tool magazine with 30 tools capacity reduces manual tool changes on complex parts
- Faster rapid traverse at 15 m/min (591 ipm) reduces non-cutting time between operations
- Superior spindle motor at 15 kW (20 HP) continuous vs 7.5 kW (10 HP) continuous
Mitsui Seiki J6CN
- Superior table size at 800 x 500 mm (31.5 x 19.7 in) vs 630 x 500 mm (24.8 x 19.7 in)
- Tighter positioning accuracy at +/-1.0 um for precision-critical work
- Tighter repeatability at +/-0.5 um for precision-critical work
- Superior spindle speed at 8,000 rpm vs 6,000 rpm
Verdict
This is a close matchup. The Mitsui Seiki H6D and Mitsui Seiki J6CN trade advantages across different specifications, making neither a clear winner on paper alone. Your decision should come down to practical factors: which dealer is closer, which control system your operators already know, what tooling ecosystem you're invested in, and which machine's specific strengths match your highest-volume work. Get quotes on both, run test cuts with your actual parts if possible, and factor in long-term service and support costs.