Menu

Technical Support

Feeds & Speeds Chart for Reamers
Feeds & Speeds Chart for Keyseats
Feeds & Speeds Chart for Counterbores
Feeds & Speeds Chart for Cutters & Saws
Feeds & Speeds Chart for Drills



Carbide Tipped Problem Solving Guide

MILLING PROBLEMS || DRILLING PROBLEMS || REAMING PROBLEMS

MILLING PROBLEMS
POSSIBLE CAUSES
POSSIBLE SOLUTIONS
1. ROUGH FINISH
Dull cutting edge
Wrong feeds & speeds
Resharpen to original tool geometry.
Increase speed - also try reduced feed.
2. EXCESSIVE
CUTTING
EDGE WEAR
Wrong feeds & speeds



Rough cutting edge

Insufficient coolant
Increase feed (should always be over .001" per
tooth) - especially when machining ductile
or free machining materials. - Also try
reduced speed.
Lightly hone cutting edge with fine grit
diamond hone.
Increase coolant flow - review type of coolant.
3. CHIPPED
CUTTING
EDGE
Poor chip removal

Recutting work hardened
chips
Vibration

Incorrect carbide grade
Use tool with larger flute space - larger
diameter or fewer flutes.
Increase coolant flow.

Increase rigidity of set-up, especially worn
tool holders.
Change to tougher carbide grade.
4. CHATTER MARKS
Insufficient machine
horsepower
Vibration
Use tool with fewer flutes as correct speeds &
feeds must be maintained.
Consider climb milling.
Use larger diameter cutter.
Resharpen tool with more clearance.
5. GLAZED FINISH
Feed too light
Dull cutting edge
Insufficient clearance
Increase feed.
Resharpen tool to original geometry.
Resharpen tool with more clearance.
6. POOR TOOL LIFE
Excessive cratering

Milling abrasive material



Milling hard material
Insufficient chip room
Milling surface scale

Delayed resharpening

Thermal cracked carbide
Increase speed or decrease feed.
Change to harder grade of carbide.
Decrease speed and increase feed.
Increase coolant flow.
Climb milling better than conventional
milling.
Reduced speed - rigidity very important.
Use larger diameter tool.
Conventional milling better than
climb milling.
Prompt resharpening to original geometry
will increase total tool life.
Increase coolant flow at all times.
Climb milling is cooler than conventional
milling.


DRILLING PROBLEMS
POSSIBLE CAUSES
POSSIBLE SOLUTIONS
1. CHIPPED CUTTING
EDGE
Excessive feed
Excessive lip relief

Vibration
Thermal cracking carbide
Reduce feed.
Reduce lip relief to provide smaller
chisel angle.
Frequently a worn drill bushing - REPLACE.
Maintain adequate coolant flow at all times
to avoid thermal shocking carbide.
2. SHORT TOOL LIFE
Drill Dwelling
Only one lip cutting
Maintain adequate feed at all times.
Regrind with equal lip heights and chisel
in center.
3. DRILL WALKS
OR DRIFTS
Unequal lip heights

Worn drill bushing
Regrind with equal lip heights and chisel
in center.
Replace drill bushing.
4. OVERSIZE HOLES
Unequal lip heights

Excessive lip relief
Worn drill bushing
Regrind with equal lip heights and chisel
in center.
Reduce lip relief to provide smaller chisel angle.
Replace drill bushing.
5. ROUGH FINISH
Dull cutting edge
Inadequate coolant
Regrind with fine grit diamond wheel.
Review type of coolant and maintain
adequate flow.


REAMING
PROBLEMS

POSSIBLE CAUSES
POSSIBLE SOLUTIONS
1. POOR FINISH
Unequal chamfers
Incorrect margins

Excessive spindle runout
Chatter
Regrind reamer with equal chamfer angle.
Regrind reamer with narrow margins for
reaming lower tensile materials.
Increase reamer back taper (will lose size faster).
Reduce speed and increase feed rate.
Use power feed unless material is hard.
Use right or left spiral fluted reamer.
Grind secondary lead angle immediately back of
45° chamfer.
2. OVERSIZE HOLE
TAPER HOLE BELL
MOUTH HOLE
POOR FINISH
Misalignment


Insufficient
cutting action
Use bushing - .0002"/.0003" over reamer diameter.
If hole location varies, use floating reamer holder.
Increase reamer back taper (will lose size faster).
Specify reamer with positive radial rake to reduce
cutting pressure - may produce slightly larger
diameter holes.
3. EXCESSIVE TOOL
WEAR
Insufficient stock for
removal


Excessive reaming
pressure


Misalignment
Decrease previous operation drill size to
allow more material for removal by reamer - leave
about 3% of hole diameter for cast iron and more
stock for non-ferrous materials.
Increase feed rate.
Reduce stock to be removed
    by increasing previous
operation drill size - leave about 3% of the hole
diameter.
See problem #2 above.
4. CROOKED HOLES
Not drilled straight
Correct previous drilling operation - reamer
will follow the drilled hole.
Increase reamer attack angle
    (chamfer) to 120°/180°
included angle.
5. TOOL BREAKAGE
Excessive reaming
pressure
Misalignment
Reduce stock to be removed - see problem
#3 above.
See problem #2 above.