Specifications

21
Threads Gear
Per Inch A B C D
12 40 65 - 30
13 40 65 60 30
14 40 65 - 35
16 40 65 - 40
18 40 65 - 45
19 40 50 60 57
20 40 65 - 50
22 40 65 - 55
24 40 65 - 60
26 40 60 - 65
28 20 65 - 35
32 20 65 - 40
36 20 65 - 45
38 20 50 60 57
40 20 65 - 50
44 20 65 - 55
48 20 65 - 60
52 20 60 - 65
GEAR CHART FOR CUTTING IMPERIAL THREADS
Examples:
1. Ref. Fig A on page 19.
To cut 12 TPI, use 40T in position A,
30T in position D,
use the 65 tooth gear in position B to connect A and D.
2. Ref. Fig B on page 19.
To cut 38 TPI, use 20T in position A
50T in position B
60T in position C
57T in position D
INDICATOR TABLE
TPI SCALE
12 1,3,5,7
13 1
14 1,5
16 1~8
18 1,5
19 1
20 1,3,5,7
22 1,5
24 1~8
26 1,5
28 1,3,5,7
32 1~8
36 1,3,5,7
38 1,5
40 1~8
44 1,3,5,7
48 1~8
52 1,3,5,7
1~8 indicates that any of the
8 lines may be used.