Flank Wear

• High cutting speed
• Chip too thin
• Insufficient coolant

• Reduce cutting speed
• Increase feed rate and reduce radial passes
• Check coolant pressure / flow direction

Fracture/Chipping

• Vibration
• High load on cutting edge

• Check stability
• Reduce feed rate
• Add radial passes

Build up Edge

• Cutting speed too low
• Insufficient coolant

• Increase cutting speed
• Check coolant pressure / flow direction

Thread Surface-Chatter Marks/Vibrations

• Feed rate is too high
• Large profile
• Thread length too long

• Reduce feed rate
• Add passes
• Add radial passes
• Reduce overhang

Thread Accuracy (GO/NOGO Gauge)

• Tool deflection
• CNC program error

• Reduce feed rate
• Add radial passes
• Use ZERO compensation
• Check CNC program

Insert/Tool Breakage

• High load on the cutting edge
• Unproper cutting conditions
• Chip evacuation
• CNC program error

• Add radial passes
• Adjust cutting conditions
• Add sufficient coolant
• Check CNC program

Tapered Thread

• Tool cutting load
• Tool overhang

• Add radial passes and/or reduce cutting conditions
• Clamp tool to the minimum overhang length

Short Tool Life

• Unsuitable cutting conditions
• Vibrations

• Reduce overhang as short as possible
• Check tool and workpiece clamping