scope:

This standard applies to spur and helical gearlng of 20 through 120 diametral pitch. Similar data for spur gears of 19.99 diametral pitch and coarser is found in USAS B6.1-1968, "Tooth Proportions for Coarse-Pitch Involute Spur Gears." (AGMA 201.02).

The tooth proportions shown herein will be suitable for many gear designs of finer than 120 diametral pitch, however, such designs should be checked for suitability, particularly in the areas of conran ratio, undercutting and clearance.

Information on standard tooth proportions for spur and helical gearing of 20 degree pressure angle and having 10 or more teeth is given in the main body of this standard. Data on 14¼ degree and 25 degree pressure angles is given in the information sheets at the back. Basic equations relati ve to the material in the standard are also given in the information sheets.