TNMG 220408 dimensions
| Inscribed circle IC | 12.7 mm |
| Cutting edge length | 22.00 mm |
| Thickness s | 4.76 mm |
| Nose radius rε | 0.8 mm |
| Corner angle | 60° |
| Clearance angle | 0° |
| Tolerance M | IC ±0.08 · corner height ±0.13 · thickness ±0.13 mm |
| ANSI equivalent (inch) | TNMG 432 |
What TNMG 220408 tells you on the shop floor
60° corner: general turning, three corners (six edges if double-sided negative); not as strong as C and W.
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.
The most common radius: a balance between strength and finish.
Typical holders for TNMG
For a negative triangular 60° insert the most common ISO 5608 holders are:
- PTGNR/L · lead angle 90°
- PTFNR/L · lead angle 90°
- PTTNR/L · lead angle 60°
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
In inches, with the ANSI designation, the same insert is TNMG 432: size in eighths of an inch, thickness in sixteenths, radius in sixty-fourths. Converting any code, both ways, is in ISO Inserts Pro.
Other TNMG sizes
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.