Posted by northern gear cutter on October 02, 2008 at 21:03:12:
In Reply to: Re: Tangential fly hobbing posted by lee on October 02, 2008 at 15:03:20:
Hi all, Thanks for the input. The way we cut wormwheels with a fly cutter is by feeding the fly tool in at a tangent to the blank the same as you would with a tapered hob. I have seen wheels cut by plunging the fly tool in on centre but this does not generate the correct tooth form.
The last two wormwheels cut have had the wrong tooth form but these were a six start and a seven start. single or two start seem to be fine although im suspecting that the problem is there on low number of starts just that its much more pronounced on large multi start wheels.
Would feeding from the left instead of the right or vice versa dpending on the hand affect tooth form ? I suppose doing a trial with a plastic blank is probably the only way to find out.