Manual
72
4. Boring
Finish boring
The nish boring tools are single-edge tools with radial micrometer
adjustment on the cutting unit head. Finishing is used when close
hole tolerances and excellent surface nish are needed.
Choose a light cutting insert with a positive cutting geometry. First
choice is knife-edge inserts (TCGT L-K). Use a small nose radius of
0.2 mm (0.008 inch), maximum 0.4 mm (0.016 inch).
Tolerance of hole diameter
For nishing with one insert, a tolerance of IT7 can be achieved in
good conditions. The tolerance will be inuenced by the clamping
of the tool holder, xtures of the component and wear of insert.
We recommend a measuring cut to decide what adjustments are
needed to compensate for tool deection. To achieve good surface
nish and close hole tolerances, it is also important to use cutting
uids to prevent recutting of chips and heat expansion of the tool
and workpiece.
Finish boring cartridge
and insert