machining worm gear wheels

This video demonstrates how I made a set of worm gear wheels using the free hobbing method.
In the first part of the video a gear hob is made from silver steel. We set up a dividing head for helical milling to mill the threads of a triple-start worm screw.
The teeth of the actual wheels are first pre-cut with a regular involute cutter and finished with the custom made gear hob.

- intro 00:00
- taking measurements 00:58
- machining the gear hob
-- grinding a stylus (D bit/single flute) cutter 01:13
-- basic turning operations 04:40
-- drilling "eccentric center holes" 07:15
-- final turning operations 08:00
-- setup for helical milling of the threads 09:08
-- helical milling ("roughing") with end mill 10:08
-- setup for triple-start thread 11:46
-- finishing the threads with stylus (D bit/single flute) cutter 18:37
-- milling relief angles (still photographs) 22:00
-- milling cutting edges 22:57
-- finished gear hob 25:02
-- heat treated gear hob 25:20
-machining the worm gear wheel(s)
-- basic turning operations 25:25
-- milling a radius 27:28
-- pre cutting (gashing) the teeth with an involute gear cutter 29:48
-- finishing with gear hob (free hobbing method) 35:36
- finished parts 43:28
- cutouts 44:41

This is the video on the restoration of the "target lathe"    • Ehrlich Lathe Restauration  
and the lathe after restoration    • Old "Oskar Ehrlich" Lathe is turning ...  
The worm wheel installed:    • 20220113 185001