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THREAD TURNING Helix (Lead) Angle Area by Using Graph φ(φL)
Helix Angle Evaluation
φ(φL)
φ(φL)
φ(φL)
T.P.I
5°
4°
2°
3°
2
Pitch / Lead [inch] 3 4 φ(φL)
1°
4.5
5
6
7
8
9
10
11.5 11
12
5/8 3/4 1/8 1 1 1/8 1 1/4 1 3/8 1 1/2 1 5/8 1 3/4 2 2 1/4 2 1/2 2 3/4 3 3 1/4 3 1/2 3 3/4 4 4 1/4 4 1/2 4 3/4 5
Diameter [inch]
Detailed View for Small Pitch/Diameter
T.P.I φ(φL) φ(φL) φ(φL) φ(φL)
13 5° 4° 3° 2°
14
16
18 φ(φL)
Pitch / Lead [inch] 19 1°
20
22
26 24
28 27
32
36
40
44
48
60 56
72 64
80
1/64 1/32 1/16 3/32 1/8 5/32 3/16 7/32 1/4 5/16 3/8 7/16 1/2 9/16 5/8 3/4
Diameter [inch]
38 ISCAR
