Thread: Forward Gears
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Bob La Londe[_2_] Bob La Londe[_2_] is offline
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Default Forward Gears

"Karl Townsend" wrote in message
...

I either have the time or the money, but never both at once. Actually I
was
looking at some of the lathe turned gear cutters.


Sounds like the story of my life. Only sometimes I have neither.



http://www.youtube.com/watch?v=8UBxNPbg0ls He talks a lot, but it's a
good
example of what I was thinking of.

Maybe an oil hardening drill rod to make the cutter. I don't know, but
this
little adventure got me reading all kinds of new stuff.


Now you're getting more advanced. Hobbing involves coordinated motion
of two axis at the same time. You'd need a good CNC 4rth axis. The
advantage is one cutter does all gears from tiny to rack. I'd start
with the involuter cutter idea.


I don't see why it needs coordinated 4th axis motion. Don't see why the
table couldn't be advanced manual by my calculation chart method just like
using an involute cutter.


You want to read Ivan Law's book, "gears and gear cutting". there's a
section in there on making involute cutters starting with round HSS
blanks to make a fly type cutter.


I just ordered a copy from Amazon. Interestingly a new copy was cheaper
than a used copy. Still a single point "fly" cutter type setup is going to
be so sloooooow.


I love my devleig boring bars with removable brazed carbide inserts. I
can calculate the exact involute shape and plot it at 50X. Lay a paper
cutout on the optical comparator with the 50X scope. Start grinding on
the baldor carbide grinder and setting the work in the comparator.
Only takes a few minutes to get the involute shape perfect.

Karl