PROBLEM SOLVING GUIDE
AVOID PROBLEMS BY CAREFUL ORIGINAL SET-UP
MACHINE CONDITION Tool holder in good condition and secure part holding fixture
TOOL CONDITION Use cutting tool recommended for material being machined. Avoid excessive tool overhang.
FEEDS & SPEEDS Start with feeds and speeds recommended for material being machined
COOLANT Coolant flow must be adequate to avoid intermittent quenching and to flush chips promptly, avoiding the recutting of hardened chips.
COUNTERBORING PROBLEMS POSSIBLE CAUSES POSSIBLE SOLUTIONS
1. ROUGH FINISH Dull cutting edge Resharpen to original tool geometry
Wrong feeds & speeds Increase speed - also try reduced feed
2. EXCESSIVE CUTTING
EDGE WEAR
Wrong feeds & speeds Increase feed (should always be over .001" per tooth) - especially when
machining ductile or free machining materials. Also try reduced speed
Rough cutting edge Lightly hone cutting edge with fine grit diamond hone
Insufficient coolant Increase coolant flow - review type of coolant
3. CHIPPED CUTTING EDGE Poor chip removal Use tool with larger flute space - larger diameter or fewer flutes
Recutting work hardened chips Increase coolant flow
Vibration Increase rigidity of set-up, especially worn tool holders
Incorrect carbide grade Change to tougher carbide grade
4. CHATTER MARKS Insufficient machine horsepower Use tool with fewer flutes as correct feeds & speeds must be maintained
Vibration Consider climb milling
Use larger diameter cutter
Resharpen tool with more clearance
5. GLAZED FINISH Feed too light Increase feed
Dull cutting edge Resharpen tool to original geometry
Insufficient clearance Resharpen tool with more clearance
6. POOR TOOL LIFE Excessive cratering Increase speed or decrease feed
Change to harder grade of carbide
Abrasive material Decrease speed and increase feed
Increase coolant flow
Hard materials Reduce speed - rigidity very important
Insufficient chip room Use larger diameter tool
Delayed resharpening Prompt resharpening to original geometry will increase tool life
Thermal cracked carbide Maintain adequate coolant flow at all times