Posted by BillS on October 16, 2009 at 14:02:29:
In Reply to: Worm Gears on a G&E Hobber. posted by Mark S on October 16, 2009 at 10:35:49:
There is a good article at:
manufacturing-single-envelope-worm-gears
I had to search for it on their site (in page 5 of archives) but it covers a lot of info on cutting worm gears.
If you use a hob cutter, the G&E is easy to setup. Lock feed and use radial infeed. G&E should have that, and a trip to set for depth. Use index gears for equivalent spur gear (Constant/T). Setting the table angle is important, since this determines the helix angle of the gear and alignment with worm. Also, use a cutter whose diameter is slightly larger than the mating worm. Depth of cut determines backlash with mating worm. There are different ways to throat the gear, but you just need to have enough clearance at root of worm.
If you use a fly cutter, your G&E must have tangential feed, and you will need to use the differential to compensate for hob travel motion.
Did I miss anything?