Whereas that would be generally true, I posit that it isn't true
for the SPECIAL CASE where the hob is traversing through the
blank in parallel with the line of action of the cutting teeth. ie,
set the hob over by its own helix angle (not to be confused with
the helix angle that you're trying to cut) and with the blank set over
at the helix angle that you _ARE_ trying to cut, then manual feed,
as for spur gears should be possible.

A picture paints a thousand words, but I ain't got one!

Which reminds me that a new S.I. Unit has been introduced,
the "milli-Helen" = it is the amount of feminine pulchritudinity that
is neccessary to be able to launch one ship.

M wrote:
Yes, I misunderstood your method. I thought you had mis-used the term
"hob". If I understand what you are asking, then the feed is an integral
part of producing the helix angle, and it would not be possible to generate
it by hand.