Value Collection 375-5156 Boring Bar M35 Cobalt 3/4 Inch Shank

Product Description

The VALUE COLLECTION 375-5156 is a right-hand boring bar machined from M35 cobalt high-speed steel, designed for precision internal boring operations on lathes and boring mills. It accepts a minimum bore diameter of 0.625 inches and reaches a maximum bore depth of 3.125 inches, making it well suited for through-bores and blind bores in medium-depth workpieces. The 3/4-inch shank diameter provides solid tool-post clamping rigidity, and the 4.875-inch overall length gives the operator adequate reach without excessive overhang. M35 cobalt construction offers improved heat resistance and edge retention compared to standard M2 high-speed steel, supporting higher cutting speeds in harder ferrous materials.

This boring bar is used in manual and CNC lathe operations for enlarging, truing, or finishing existing bored holes in steel, cast iron, stainless, and similar ferrous materials. It is a common choice for job-shop machinists, tool-and-die makers, and maintenance machinists who need a reliable single-point boring tool for moderate-depth internal turning work. The right-hand cutting direction is the standard orientation for conventional lathe setups.

Key Features

• M35 cobalt HSS construction for improved heat resistance and edge retention over standard HSS
• Minimum bore diameter of 0.625 inches suits a wide range of bore-finishing applications
• Maximum bore depth of 3.125 inches handles medium-depth through and blind bores
• 3/4-inch shank diameter for secure, rigid tool-post or boring-head clamping
• 4.875-inch overall length balances reach and overhang rigidity
• Right-hand cutting direction for conventional lathe orientation

Compatibility

Designed for use in standard tool-post holders and boring heads accepting a 3/4-inch round shank, on manual engine lathes and CNC turning centers with appropriate tooling blocks.

Installation Notes

Installation and tool changes must be performed with the machine powered down and spindle fully stopped. The shank should be clamped with the minimum overhang necessary to reach bore depth, as excessive overhang increases chatter risk. A qualified machinist should verify tool height, cutting geometry, and workholding security before initiating a cut. Follow shop safety practices and applicable OSHA machine-guarding requirements when operating any lathe or boring mill.