■ Functions of cutting edge angles Material Technical Guidance The Basics of Milling
Symbol
Function
Effect
Available in positive to negative (large to small) rake angles. Typical combinations: Positive and Negative, Positive and Positive, Negative and Negative
(1) (2)
Axial rake angle Radial rake angle
A.R. R.R.
Determines chip evacuation direction, adhesion, thrust, etc.
(3) Approach angle
A.A.
Determines chip thickness and chip evacuation direction
Large: Thin chips
Small cutting force
Positive (Large): Excellent
(4) True rake angle
T.A.
Effective rake angle
machinability and low chip adhesion. Low cutting edge strength Negative (Small): S trong cutting edge and easy chip adhesion Positive (Large): Excellent chip control and small cutting force. Low cutting edge strength
N
(5) Cutting edge inclination angle
I .A.
Determines chip control direction
(6) Face cutting edge angle
F.A. Determines surface finish roughness Small: Excellent surface roughness
Determines cutting edge strength, tool life, chattering
(7) Relief angle
Inclination angle (I.A.) chart
True rake angle (T.A.) table
+30° +25° +20° +15° +10° +5° 0° -5° -10° -15° -20° -25° -30°
+30° +25° +20° +15° +10° +5° 0° -5° -10° -15° -20° -25° -30°
-30° -25° -20° -15° -10° -5° 0° +5° +10° +15° +20° +25° +30°
+30° +25° +20° +15° +10° +5° 0° -5° -10° -15° -20° -25° -30°
True rake angle T.A.
Inclination angle I.A.
+30° +25° +20° +15° +10° +5° 0° -5° -20° -25° -10° -15° -30°
-30° -25° -20° -15° -10° -5° 0° +5° +20° +25° +10° +15° +30°
(2)
1
(1)
(4)
(4)
(2)
(3)
(3)
40°45°50°55° 60° 65° 70° 75° 80° 85° 90°
40°45°50°55° 60° 65° 70° 75° 80° 85° 90°
0° 5° 10° 15° 20° 25° 30° 35°
0° 5° 10° 15° 20° 25° 30° 35°
Approach angle A.A.
Approach angle A.A.
= +10° = -30° = 60° }
= -10° = +15° = 25° }
Example:(1) A.R. (2) R.R. (3) A.A.
(Axial rake angle) (Radial rake angle) (Approach angle)
Example:(1) A.R. (2) R.R. (3) A.A.
(Axial rake angle) (Radial rake angle) (Approach angle)
-> (4) I (inclination angle) = -15°
-> (4) T.A. (True rake angle) = -8°
Formula: tan T.A.=tan R.R./cos A.A. + tan A.R./sin A.A.
Formula: tan I.R.=tan A.R./cos A.A. - tan R.R./sin A.A.
■ Rake angle combination and features
Double Positive type
Negative - Positive type
Double Negative type
Edge combination and chip evacuation A.R.: Axial rake angle R.R : Radial rake angle A.A.: Approach angle
A.A. (15 to 30°)
A.A. (15 to 30°)
A.A. (30 to 45°)
A.R.
A.R.
A.R.
Neg.
Pos.
Pos.
: Chip and evacuation direction : Cutter rotation direction
R.R. Pos.
R.R. Neg.
R.R. Neg.
Economical design enabling use of both sides of insert Strong cutting edge
Excellent chip evacuation and sharpness Only single-sided inserts can be used Machining of steel, cast iron, and stainless steel, with suitable strength and good evacuation
Advantages
Good sharpness
Only single-sided inserts with a lower cutting edge strength can be used Machining of aluminum alloy and other materials requiring sharpness
Disadvantages
Dull cutting action
For hard materials such as cast iron or poor surfaces such as castings
Applications
Cat. No.
ALNEX, HF, WAX
WGX, WFX, RSX, WEZ
TSX, DGC, DFC, DNX
Chips (Ex.)
· Part material: Alloy Steel · v c =430 SFM f z =.009 in./t a p =.118”
N54
Made with FlippingBook flipbook maker