Taylor Tool carries a wide variety of special taps and dies. Below you will find a short list of some of the taps and dies we carry and how they are furnished. For sizes and pricing contact us by email (colleen@taylortool.ca) or by phone (519-658-9378).
Special Taps and Dies
Commercial Ground Thread - American
National Form
The following tables and formulae are used in determining the limits and tolerances for ground thread taps having special diameter or special pitch or both. Lead Tolerance...a maximum lead error of plus or minus 0.0005 inch in one inch of thread is permitted.
Angle Tolerance:
| Threads per inch | Error in Half Angle |
| 4 to 5 1/2 incl. | 20' plus or minus |
| 6 to 9 incl. | 25' plus or minus |
| 10 to 56 incl. | 30' plus or minus |
Formulae:
A = Major Diameter Tolerance
B = Amount over basic for minimum pitch diameter
C = A constant to add:
35% of the theoretical truncation for 4 to 5 threads per inch
40% for 5 1/2 to 12 threads per inch
45% for 13 to 56 threads per inch.
To nearest 0.005 inch for 8 or more threads per inch and to nearest 0.001
inch for less than 8 threads per inch.
D = Pitch diameter tolerance:
Maximum Major Diameter = Basic plus C
Minimum Major Diameter = Maximum minus A
Maximum Pitch Diameter = Minimum plus D
Minimum Pitch Diameter = Basic plus B
Values for A, B, C, and D:
|
B
|
|||||||
|
Threads per inch
|
A
|
to 3/4 inch incl.
|
Over 3/4 inch to 1 1/2 inch incl.
|
Over 1 1/2 inch to 2 1/4 inch incl.
|
Over 2 1/4 inch
|
C
|
D
|
|
56
|
0.0010
|
0.0002
|
0.0010
|
0.0015
|
0.0020
|
0.0015
|
0.0010
|
|
48
|
0.0010
|
0.0002
|
0.0010
|
0.0015
|
0.0020
|
0.0020
|
0.0010
|
|
44
|
0.0010
|
0.0002
|
0.0010
|
0.0015
|
0.0020
|
0.0020
|
0.0010
|
|
40
|
0.0010
|
0.0002
|
0.0010
|
0.0015
|
0.0020
|
0.0025
|
0.0010
|
|
36
|
0.0010
|
0.0002
|
0.0010
|
0.0015
|
0.0020
|
0.0025
|
0.0010
|
|
32
|
0.0010
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0030
|
0.0010
|
|
28
|
0.0010
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0035
|
0.0010
|
|
24
|
0.0010
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0040
|
0.0010
|
|
20
|
0.0010
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0050
|
0.0010
|
|
18
|
0.0010
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0055
|
0.0010
|
|
16
|
0.0010
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0060
|
0.0010
|
|
14
|
0.0010
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0070
|
0.0010
|
|
13
|
0.0010
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0075
|
0.0010
|
|
12
|
0.0010
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0075
|
0.0010
|
|
11
|
0.0010
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0080
|
0.0011
|
|
10
|
0.0015
|
0.0005
|
0.0010
|
0.0015
|
0.0020
|
0.0090
|
0.0011
|
|
9
|
0.0015
|
....
|
0.0010
|
0.0015
|
0.0020
|
0.0100
|
0.0012
|
|
8
|
0.0015
|
....
|
0.0010
|
0.0015
|
0.0020
|
0.0110
|
0.0014
|
|
7
|
0.0020
|
....
|
0.0010
|
0.0015
|
0.0020
|
0.0120
|
0.0015
|
|
6
|
0.0020
|
....
|
0.0010
|
0.0015
|
0.0020
|
0.0140
|
0.0018
|
|
5 1/2
|
0.0025
|
....
|
....
|
0.0015
|
0.0020
|
0.0160
|
0.0020
|
|
5
|
0.0025
|
....
|
....
|
0.0015
|
0.0020
|
0.0160
|
0.0020
|
|
4 1/2
|
0.0025
|
....
|
....
|
0.0015
|
0.0020
|
0.0170
|
0.0020
|
|
4
|
0.0025
|
....
|
....
|
0.0015
|
0.0020
|
0.0190
|
0.0020
|
Additional information is available for other special taps and dies. Please inquire by email (colleen@taylortool.ca) or by phone (519-658-9378).
J. A. M. TAYLOR TOOL CO. LIMITED | 4 GOEBEL AVE. CAMBRIDGE, ON N3C 1Z1 | TEL: 519.658.9378 | FAX: 519.658.6799
