Aluminum body made lighter for higher rpm/ Poly Crystaline Diamond
Rotary Milling Cutter
Each cutting edge spins on a bearing/ should cause even wear on each cutting edge
Face and Side Cutting
Slots and Grooves
Roughing Endmill (Porcupine Cutter)
High metal removal/ multiple inserts/ leaves rough finish/ not end cutting
Endmills
Used for removing material from the top or sides of a work piece/ 2,3,4,6,8 teeth/ some endcutting/ limited depth of cuts/ more precise/ various ground radii possible/ regrindable/ long cut length on walls
Slitting Saws
for producing very thin slots
Dovetails and T-slot cutters
for making dovetail shapes and woodruff keyseats
Special Radius Cutter
produces a corner radius at a customer specified size
Tailor Made Custom Cutters
To produce unique profiles/ CNC ground/ Virtually any shape possible
Thread Milling
Used to make large threaded holes without using a tap
70% Engagement Rule of Thumb
2/3 (70%) of the cutter needs to be engaged in the cut and 1/3 (30%) needs to be out of the cut
Chip formation lead angles
90 degree creates a big chip/ 45 degrees creates a thinner chip
Coolant in Milling Rules of Thumb
Never Use Coolant when Milling
Cutter with Round Inserts
Pros - Robust milling cutters/ very flexible for face milling and profiling/ high performance multi-purpose cutters
Cons - round inserts requires more stable conditions
Forces - radially/axially/and in between
45 degree face and shoulder mill
Pros - general choice for face milling/ balanced radial and axial cutting forces/ smooth entry into cut
Cons - max cutting depth 6-10mm
Forces - equal axial and radial forces
90 degree face and shoulder mill
Pros - great versatility/ first cutter generating true 90 degree square cuts / light cutting inserts with true four edges
Cons - Max cutting depth .157in
Forces - only radial
Low Pitch (Coarse pitch)
Fewer inserts (4)/ lower feedrate/ less vibration
Medium Pitch (Close pitch)
Double inserts (8) higher feedrate/ more vibration
High Pitch (extra close pitch)
Inserts further apart, higher stability
How do you prevent vibration in milling?
Fewer teeth require less HP and induce less axial pressure. Moving the cutter off centre creates less vibration. Differential pitch where the teeth are unevenly distributed around the mulling cutter creates varying frequencies to combat harmonics.