(1) NT is the connecting link between tooth
elements and gear elements.
(2) To completely calculate a gear, one
tooth and one gear element must be known.
(3) For every tooth in the gear there is a
circular pitch on the pitch circle.
(4) For every tooth in the gear there is an
addendum on the pitch diameter.
10. PD = ADD × NT
11. OD = ADD × (NT + 2)