Welcome to the Troubleshooting Guide. In this section, end milling problems are addressed with potential solutions listed below. Choose from the following problems:


Chip Packing Feed per tooth too high
Not enough chip room
Not enough coolant
Lower feed rate
Use end mill fewer flutes
Use more coolant to flush out chips
Rough finish Feed too fast
Slow speed
Too much wear
Feed per tooth too high
Slow down to correct feed
Use higher speed
Regrind sooner
Lower feed rate
Burr Dull cutting edge
Improper cutting angle
Regrind sooner
Change to correct cutting angle
Wandering Machine/Holder runout
Not enough rigidity in machine/holder
Not enough flutes
Tool deflection
Repair machine or holder
Change machine or holder
Use end mill with more flutes
Choke up on shank or reduce feed rate
Chipping Feed too fast
Feed too fast on first cut
Not enough rigidity of machine/holder
Loose holder
Loose vise
Lack of rigidity (tool)
Teeth too sharp
Lower feed rate
Lower feed on intial contact
Change to rigid machine/holder
Tighten tool holder
Tighten workpiece fixture
Choke up on shank; use shorter tool
Choose tool with correct primary relief angle
Wear Speed too fast
Hard material
Feed too slow
Improper cutting angle
Primary relief angle too small
Slow down speed, use more coolant
Use better grade for cutter material, add coating
Increase feed speed
Change to correct cutting angle
Increase primary relief angle
Breakage Feed too fast
Chip load per tooth too great
Flute length too long
Long overall length
Too much wear
Slow down feed
Adjust to smaller chip load per tooth
Choke up on shank
Use shorter end mill
Regrind sooner
Chattering Feed and speed too fast
Poor rigidity of machine/holder
Relief angle too large
Loose workpiece holder
Cutting too deep
Flute length too long
Long overall length
Adjust feed and speed
Use better machine/holder
Change to smaller relief angle
Hold workpiece tighter
Change to smaller depth of cut
Choke up on shank
Use shorter end mill