Mitsui Seiki J7CN
Key Specifications
X Travel
Y Travel
Z Travel
Spindle Taper
Tool Capacity
Table Size
How much does the Mitsui Seiki J7CN cost?
Estimated price range
Our best estimate for a cnc boring machine in this class — not a quote from Mitsui Seiki. Configuration moves it a long way.
Overview
With 1,530 mm (60.23 in) of X travel and a 1,830 x 1,200 mm (72.04 x 47.24 in) table, the Mitsui Seiki J7CN is the larger sibling of the J6CN boring machine. It takes workpieces up to 2,000 kg (4,400 lbs) and is listed with a positioning accuracy of ± 0.001 mm (0.00004 in).
What grows over the J6CN is the envelope, not the spindle. X goes from 1,020 mm (40.15 in) on the J6CN to 1,530 mm (60.23 in), Y from 760 mm (29.92 in) to 1,020 mm (40.15 in), and table load from 1,200 kg (2,645 lbs) to 2,000 kg (4,400 lbs). Spindle power is listed as AC 10 kW (7 hp) here, and the J6CN is listed with the same AC 10 kW (7 hp) and the same 300 mm (11.81 in) of Z travel. A buyer choosing between them is choosing part size only.
Height is handled by the W axis, 920 mm (36.25 in) here, with a maximum of 1225 mm (48.2 in) from table top to spindle nose. The columns stand 1,600 mm (62.99 in) apart. W moves at 560 mm/min (22 ipm) in rapid, so it is positioned for the job and not used as a working axis between holes; X and Y rapid at 5,080 mm/min (200 ipm) and Z at 3050 mm/min (120 ipm).
The spindle runs from 40 to 3,200 RPM in a quill of 125 mm (5 in), 145 mm (5.7 in) at the nose. Taper is ISO no. 45 NT, with Cat 45 and a 50 taper offered as options. Fine feeds start at 0.1 mm/min and repeatability is ± 0.0005 mm (0.00002 in). An ATC is optional, as 20ATC or 60ATC.
Plan the building around it. The machine is 7,400 x 5,730 mm (290 x 225 in) without guarding, ATC or coolant system, and weighs 14,000 kg (30,800 lb).
Full Specifications
| Parameter | Value |
|---|---|
| X-Axis Travel | 1,530 mm (60.23") |
| Y-Axis Travel | 1,020 mm (40.15") |
| Z-Axis Travel | 300 mm (11.81") |
| Travel W | 920 mm (36.25") |
| Distance Between Columns | 1,600 mm (62.99") |
| Max Distance Table Top to Spindle Nose | 1225 mm (48.2") |
| Table Size | 1,830 x 1,200 mm (72.04" x 47.24") |
| Max Table Load | 2,000 kg (4,400 lbs) |
| Quill Diameter | 125 mm - 5" ,(145 mm - 5.7" at nose) |
| Spindle Diameter | 75 mm (3") |
| Spindle Speed | 40~ 3200 RPM |
| Spindle Taper | ISO no. 45 NT (Cat 45 -opt) (opt. 50 Taper) |
| Spindle Motor Power | AC 10 kW (7 hp) |
| Rapid Traverse Xy | 5,080 mm/min. (200 ipm) |
| Rapid Traverse W | 560 mm/min. (22 ipm) |
| Rapid Traverse Z | 3050 mm/min (120 ipm) |
| Fine Feed Xy | 0.1 - 2000 mm/min (0.0039 – 78.7 IPM) |
| Fine Feed Z | 0.1 - 2,000 mm/min. (0.004 ~ 80 ipm) |
| Positioning Accuracy | ± 0.001 mm (0.00004") |
| Repeatability | ± 0.0005 mm (0.00002") |
| Tool Capacity | Option: 20ATC; 60ATC |
| Work Handling | Manual 0-point; Robot Loader |
| Machine Length | 7,400 mm (290") (w/o guarding, ATC or coolant system) |
| Machine Width | 5,730 mm (225") (w/o guarding, ATC or coolant system) |
| Machine Weight | 14,000 kg (30,800 lb.) |
| CNC Control | FANUC 30i-B-Plus with Panel iH Pro |
Specifications sourced from mitsuiseiki.com — verified 2026-10-03
Strengths & Limitations
Strengths
- 1,830 x 1,200 mm (72.04 x 47.24 in) table rated for 2,000 kg (4,400 lbs)
- 1,530 mm (60.23 in) of X and 1,020 mm (40.15 in) of Y travel
- ± 0.001 mm (0.00004 in) positioning accuracy and ± 0.0005 mm (0.00002 in) repeatability
- 920 mm (36.25 in) W axis with 1225 mm (48.2 in) from table top to spindle nose
- 1,600 mm (62.99 in) between columns
Limitations
- Same AC 10 kW (7 hp) spindle power as the smaller J6CN, so the bigger frame brings no extra cutting power
- Z travel is 300 mm (11.81 in); deeper reach depends on the W axis, which rapids at 560 mm/min (22 ipm)
- Maximum spindle speed is 3,200 RPM, a limit for small cutters
- Occupies 7,400 x 5,730 mm (290 x 225 in) before guarding, ATC or coolant system, and weighs 14,000 kg (30,800 lb)
- The ATC is optional (20ATC or 60ATC)
Best For
Frequently Asked Questions
01
The table is 1,830 x 1,200 mm (72.04 x 47.24 in) and carries up to 2,000 kg (4,400 lbs). Travels are 1,530 mm (60.23 in) in X and 1,020 mm (40.15 in) in Y. The distance between columns is 1,600 mm (62.99 in) and the maximum distance from table top to spindle nose is 1225 mm (48.2 in).
02
No. Spindle power is listed as AC 10 kW (7 hp) on the J7CN and on the J6CN. The J7CN is the larger machine, at 14,000 kg (30,800 lb) against 9,000 kg (19,800 lbs) for the J6CN, with longer travels and a higher table load.
03
Rapid traverse is 5,080 mm/min (200 ipm) in X and Y, 3050 mm/min (120 ipm) in Z and 560 mm/min (22 ipm) in W. Fine feed is 0.1 to 2,000 mm/min in X, Y and Z.
04
Mitsui Seiki lists a machine length of 7,400 mm (290 in) and a width of 5,730 mm (225 in), both without guarding, ATC or coolant system. Weight is 14,000 kg (30,800 lb). Allow extra room for whichever of those items the machine is ordered with.
