Problems

Possible causes

Actions to be taken

Chips

1. Higher feed-rate
2. Up-ward milling
3. Too sharp of teeth
4. Vibration
5. Shake overhanging longer
6. Low milling speed
7. Milling cutter loosened
8. Work piece loosened

1. Slow down feed-rate
2. Down-ward milling
3. Make cutting edge dull——chamfered or rounded using oil stone
4. Adjust RPM
5. Decrease overhanging length
6. Increase RPM or replace milling cutter with larger helix angle
7. Adjust chuck & collet for better accuracy
8. Tighten work piece

Wear

1. Cutting speed is too higher
2. Feed rate is too lower
3. Up-ward milling
4. Material too hard
5. Debris blocked

1. Slow down cutting speed
2. Increase feed rate
3. Down -ward milling
4. Replace another mill to fit to material
5. Focus Air flow or coolant flow in grinding area

Milling cutter broken

1. Chip or worn
2. Feed rate is too high
3. Grinding force is too higher
4. Cutter overhanging length longer

1. Re-forming
2. Decrease feed rate
3. Decrease feed rate, increase RPM
4. Shorten overhanging length.

Surface finish

1. Vibration
2. Outflow
3. Worn
4. Higher feed，slow feed rate

1. Optimize grinding settings
2. Increase milling rate，increase helix angle or down-ward milling
3. Re-forming
4. Slow feed and increase cutting rate

Accuracy

1. Milling settings

Feed rate higher
Feed higher

1. Teeth is insufficient
2. Mill error

1. Optimize milling settings

Decrease feed rate
Decrease feed

1. Replace miller with more teeth
2. Increase diameter，decrease overhanging length

Problems

Possible causes

Actions to be taken

Tip Stuck

1. Cutting speed lower
2. Chamfering wider
3. Cutting teeth width smaller

1. Increase cutting speed
2. Decrease chamfering width
3. Increase coating width

Tip fracture

1. System rigidity weakened
2. Clamping run-out
3. Feed speed higher

1. Strengthen clamping
2. Improve concentricity
3. Decrease feed speed

Excessive worn -out

1. Cutting speed higher
2. Feed speed lower
3. Relief angle smaller

1. Decrease cutting speed
2. Increase feed speed
3. Increase relief angle

Cutting edge worn- out

1. Clamping rigidity weakened
2. Feed higher
3. Wear width larger

1. Check clamping and fixture
2. Slow down cutting speed
3. Decrease wear width

Chisel edge worn-out

1. Drilling tip with larger run-out
2. Clamping rigidity weakened
3. Asymmetric teeth
4. Feed higher
5. Chamfering wider

1. Check tip run-out
2. Check clamping
3. Check symmetry for tip & teeth
4. Increase cutting speed, decrease feed
5. Decrease chamfering width for teeth

Tip worn-out

1. Cutting speed higher
2. Feed smaller
3. Insufficient coolant
4. Tip without chamfer

1. Decrease cutting speed
2. Increase feed
3. Adjust coolant flow & pressure
4. Increase chamfer for tip

Hole offset

1. Clamping rigidity
2. Clamping concentricity
3. Chisel edge longer

1. Check clamping
2. Improve concentricity
3. Re-grind chisel edge

Rougher finish inside of hole

1. Clamping rigidity
2. Concentricity
3. Insufficient coolant
4. Excessive worn-out

1. Fasten clamping
2. Improve concentricity
3. Adj. coolant flow & pressure
4. Timely re-grind drill