Sumitomo unveils BSME and SEXC micro-boring bars
Holes as small as 2.5 mm diameter in hardened materials can be finish-bored and faced with Sumiboron CBN tools, following Sumitomo Electric Hardmetal's development of its BSME and SEXC series of boring bar tooling.
The BSME tool has a brazed CBN cutting edge on a carbide tool shank, which creates added stiffness, for bore sizes between 2.5 mm diameter by up to 5.3 mm deep, to 5 mm by 20.3 mm deep.
Likewise, the SEXC version features a two-corner, indexable CBN insert able to machine bores from 4 mm diameter by 8 mm in depth, to 6 mm diameter by 18 mm deep. For this insert, there are two grades of CBN available - BN2000 and BN7000 - each with a 0.2 mm nose radii. BN2000 has a honed preparation to the insert's sharp edge, while BN7000 maintains a normal sharp edge.
