The following rules and examples show how the table is used:
Rule 1.—Given —— number of teeth and pitch; to find —— pitch diameter.
Select from table in columns opposite the given pitch—
First, the value corresponding to the number of units in the number of teeth.
Second, the value corresponding to the number of tens, and multiply this by 10.
Third, the value corresponding to the number of hundreds, and multiply this by 100. Add these together, and their sum is the pitch diameter required.
Example.—What is the pitch diameter of a wheel with 128 teeth, 11⁄2 inches pitch?
We find in line corresponding to 11⁄2 inch pitch—
| Pitch | diameter for | 8 | teeth | 3.81 | 97 |
| „ | „ | 20 | „ | 9.54 | 9 |
| „ | „ | 100 | „ | 47.75 | |
| „ | „ | 128 | „ | 61.11 | 87 |
| Or about 611⁄8′′. Answer. | |||||
Rule 2.—Given —— pitch diameter and number of teeth; to find —— pitch.