CNMA 120412 dimensions
| Inscribed circle IC | 12.7 mm |
| Cutting edge length | 12.90 mm |
| Thickness s | 4.76 mm |
| Nose radius rε | 1.2 mm |
| Corner angle | 80° |
| Clearance angle | 0° |
| Tolerance M | IC ±0.08 · corner height ±0.13 · thickness ±0.13 mm |
| ANSI equivalent (inch) | CNMA 433 |
What CNMA 120412 tells you on the shop floor
80° corner: strong yet versatile, turns and faces with the same insert.
Double-sided negative insert: edges on both faces, stronger and cheaper per edge. Needs a rigid machine and clamping; not for small bores.
Pressed, medium tolerance: economical, fine for roughing and where you do not need repeatability to a few hundredths of a mm at every insert change.
Large radius: strong edge, takes high feeds. More radial force, watch slender parts.
Typical holders for CNMA
For a negative rhombic 80° insert the most common ISO 5608 holders are:
- PCLNR/L · lead angle 95°
- PCBNR/L · lead angle 75°
- DCLNR/L · lead angle 95°
The final R or L means right or left hand. Shank size, length and the exact clamping are in the manufacturer's catalogue.
Toolholders that take it
- PCLNR 2020K12
- PCLNR 2525M12
- PCLNR 3232P12
- PCBNR 2525M12
- MCLNR 2525M12
- DCLNR 2020K12
- DCLNR 2525M12
- S32U-PCLNR12
- S40V-PCLNR12
In inches, with the ANSI designation, the same insert is CNMA 433: size in eighths of an inch, thickness in sixteenths, radius in sixty-fourths. Converting any code, both ways, is in ISO Inserts Pro.
Other CNMA sizes
Same size, other version
Designation to ISO 1832; reference tables: Mitsubishi Materials turning catalogue (insert identification). Holders to ISO 5608. Chipbreaker, grade and cutting data differ between manufacturers: the catalogue of the insert you use is what counts.