Cleveland
Cleveland Cobalt M42 Rectangular Tool Bit 856 1/4X3/8 In
Cobalt M42 rectangular tool bit for lathe work, 1/4 in by 3/8 in cross-section, non-bevelled for right- or left-hand use
- M42 cobalt steel resists wear at high cutting speeds
- Rectangular 1/4 × 3/8 in blank fits standard tool holders
- 2 1/2 in overall length provides rigid support in the cut
- Right- and left-hand geometry allows versatile lathe operations
- Non-bevelled face simplifies custom grinding for specific profiles
Cobalt M42 Rectangular Tool Bit
The Cleveland Cobalt M42 rectangular tool bit is a lathe tool blank intended for machinists who need a durable cobalt substrate for general-purpose turning. It measures 1/4 in wide by 3/8 in high by 2 1/2 in long and is supplied in a non-bevelled, right-and-left-hand configuration. The M42 grade provides elevated hot hardness for extended edge life in ferrous and non-ferrous materials.
Sustained Cutting Performance
Under continuous cutting the cobalt matrix resists thermal softening better than standard high-speed steel, allowing the edge to retain hardness at elevated temperatures generated during prolonged passes. The rectangular cross-section offers consistent support along the tool holder, reducing deflection when feed rates are maintained over long cycle times. This stability helps preserve dimensional accuracy on workpieces that require extended material removal.
Application Limits
The blank is ground to the stated dimensions only; no chip-breaker geometry, coating or pre-formed relief angles are included, so the user must grind appropriate rake and clearance angles for the specific workpiece material. It is not suited for interrupted cuts that exceed the toughness of the M42 grade or for operations requiring a bevelled tip profile. Buyers needing a ready-to-use insert with a chip-control geometry or a different shank size will need a different tool form.
Highlights
- M42 cobalt steel resists wear at high cutting speeds
- Rectangular 1/4 × 3/8 in blank fits standard tool holders
- 2 1/2 in overall length provides rigid support in the cut
- Right- and left-hand geometry allows versatile lathe operations
- Non-bevelled face simplifies custom grinding for specific profiles
Specifications
| Brand | CLEVELAND |
|---|
Questions about this item
Will the Cobalt M42 bit generate excess heat during prolonged lathe work?
Cobalt M42 retains hardness at high cutting temperatures, reducing thermal buildup during extended turning operations.
What tool holder or lathe setup is required to use this 1/4 x 3/8 in rectangular blank?
A standard tool post or quick-change holder that accepts 1/4 in wide by 3/8 in high rectangular blanks is needed.
Can this non-beveled blank be used on an older manual lathe with right-hand and left-hand tooling?
Yes, the right-and-left-hand design suits both conventional and older manual lathe setups.
Also in this aisle
People compared these
Same shelf, same checkout — eight coins and a 30-minute rate lock.
