Metal cutting tool

A metal cutting tool comprising an exchangeable cutting insert having a body portion and a cutting head portion;

• said cutting head portion comprising an upper rake surface and a substantially continuous front relief flank surface, defining between them a cutting edge;
• and a cutting insert holder formed with a pair of clamping jaws releasably clamping said insert in said holder, a first of said clamping jaws clampingly abutting an upper surface of said body portion, a second of said clamping jaws having a front end surface and an upper surface oriented transversely to said front end surface and clampingly abutting a base of said body portion, said upper surface of the second clamping jaw having a surface portion projecting beyond a base edge of the front relief flank surface of the insert;
• a coolant flow channel formed in said holder having an inlet adapted to be coupled to a coolant flow supply;
• a downstream portion of said channel having an outlet formed in said surface portion in an immediate vicinity of said base edge, and being so formed that a coolant outflow from said outlet is directed substantially parallel to said relief surface.

A metal cutting tool comprising, in combination:

• a cutting insert having
• a base,
• an upper rake surface,
• a substantially continuous front relief flank surface,
• a cutting edge defined between said upper rake surface and said front relief flank surface, and
• a base edge defined between said front relief flank surface and said base, and
• a cutting insert holder adapted to retain said insert, said holder having
• a front end surface;
• a clamping surface abutting said base and oriented transversely to said front end surface, a projecting portion of said clamping surface extending beyond said base edge, said projecting portion having an upper surface oriented at an angle .alpha., 0.degree..ltoreq..alpha..ltoreq.30.degree., with respect to said clamping surface abutting said base;
• a coolant flow channel formed in said holder, said channel having a downstream portion, and
• a coolant flow channel outlet formed in said projecting portion of said clamping surface, said downstream portion and said channel outlet arranged such that a coolant outflow from said outlet is directed substantially parallel to said relief flank surface.