wormwheel/gear-sector-hobbing on rotary axis with G33.1

Hello LinuxCNC-friends!

I don't wanted to hijack this thread so i open a new one, i think i have the exact same problem: forum.linuxcnc.org/26-turning/38148-lath...-tailstock-as-w-axis

I have retrofitted a DECKEL FP3NC and a Walter dividing head and i try to make - as Andy Pugh posted - a part with an arm and a worm sector.
So sadly i can't use andy's great gearhobbing function because it would crash in the work at some angle.

andypugh wrote:

The best solution would be to extend G33.1 to all axes. (you can imagine using a rotary axis to cut a partial worm sector.....)
But it looks like that would be a significant undertaking.

I mounted an encoder to the main spindle (normal 3~ motor with gear box) and rigid tapping with G33.1 works like a charme. So if i could use the A-axis instead of Z it would be dead simple and the perfect solution and i could hob the part in multiple passes.

Maybe someone has another idea how to get this working. For the part itself i have a plan B and C, i can make it in a two part design or hob it on the lathe with a jip or or.... But i love LinuxCNC and i want to give it a second attempt.

 



Greatings from Bavaria
Tom

If there is some room to over-run, you could, in theory, run the hobbing setup and reverse the spindle at the end of sector travel, stop the feed, wait until at start of travel, re-start the spindle and the feed.

But, really, for a sector it is probably easier to use an involute cutter.

There is the possibility of generating teeth one at a time.