Figure 14-26.--Development of setover and depth increase.
9. Diametral pitch (DP)
select a cutter. The only way to select a cutter is by sight.
Get a large selection of bevel gear cutters, then match
one of them to the side of a good tooth.
To find the amount of setover, first establish the
circular pitch angle
One circular pitch equals
360°. Therefore, you can divide 360° (one circular
pitch) by the number of teeth (NT) to find the circular
METHOD OF MANUFACTURE
You can solve for the amount of
If you buy a stub tooth gear cutter, you can
manufacture a straight or helical stub tooth gear by
Setover = Root radius × Tan
using the procedure you use for spur and helical gears.
If you use a fly cutter, use the old gear as a pattern to
Where the root radius is the outside diameter (OD)
grind a single-point tool bit to the desired shape.
divided by 2 minus the whole depth (WD).
A properly fitted gear must have a setover and a
Root radius =
depth increase. You should calculate these after you