Posted by BillS on December 14, 2013 at 15:05:04:
In Reply to: Hobbing a 64deg helix angle spiral gear. posted by Ron V on December 10, 2013 at 19:12:10:
Hi Ron,
That video is beautiful! It reminds me of a response to a post about high angles and cutting forces in the same tangent direction as work piece turns.
Your situation is small pitch and large machine/table mass, so you wouldn't expect the work table drive backlash to unload and jump.
There is an article by August Lehman where it looked like that was happening, and his cutter was busted. He used a "brake" around the workpiece to put drag on the workpiece drive. I thik this dampened vibration and kept the drive from unloading and jumping.
His article is shown on this site at the "Articles" link at this homepage.