Drilling troubleshooting Chart

 

 

PROBLEM CAUSES SOLUTIONS
CHIPPING OR BREAKAGE Poor chip evacuation due to insufficient coolant pressure and/or volume Increase coolant flow
Deflection Reduce overhang
Misalignment Check concentricity not to exceed +/- .005 tir
Speed too slow, feed too light Increase speed and/or feed
Wrong chipbreaker geometry Use stronger chipbreaker (3P)

 

 

PROBLEM CAUSES SOLUTIONS
CORNER OF INSIDE INSERT CHIPS AT CENTER High cutting force at center of drill Use tougher grade or uncoated grade in inside position

 

 

PROBLEM CAUSES SOLUTIONS
LOUD, ROUGH CUTTING Excessive thrust force Reduce feed, increase speed
Re-cutting chip Increase coolant flow

 

 

PROBLEM CAUSES SOLUTIONS
LONG UNBROKEN CHIP Insufficient coolant pressure and volume Increase coolant flow
Feed rate too light Increase feed
Wrong chipbreaker geometry Use more positive geometry: (1P)

 

 

PROBLEM CAUSES SOLUTIONS
CHATTER Vibration Check setup and part rigidity
Poor chip control Increase coolant flow
Drill not properly seated in holder Check set-up

 

 

PROBLEM CAUSES SOLUTIONS
HOLE SIZE TOO LARGE Drill misaligned Correct misalignment


PROBLEM CAUSES SOLUTIONS
FRACTURING OF DRILL Improper seating of inserts Check insert seating
Unstable spindle Use rigid machine
Insufficient horsepower Reduce feed or change machines
Excessive thrust force Reduce feed


PROBLEM CAUSES SOLUTIONS
SHORT TOOL LIFE Excessive insert wear Lower cutting speed or change grade
Lack of rigidity Check set-up and spindle
Improper coolant Check type of coolant and mixture