Gear for the gearbox of a drill press

In this video, I make two gears, the first of which fails.
In this video I use:
- Weiler Matador SV (1972) Lathe
- Schaublin SV-51 (1955) Milling machine
- Solberga (1975) Drill press
Chapters:
0:00:00 Opening animation
0:01:01 Introduction
0:01:30 Basic settings for gear milling
0:03:52 Choosing a modular milling wheel
0:06:03 Setting the cutting depth
0:07:17 Choosing the right index disc for the dividing head
0:09:28 Layout and use of dividing head sector arms
0:12:39 Setting cutting speed and feed
0:13:30 Feedback from comments
0:16:00 I mill the first gear and it fails
0:20:06 Analysis of the failure
0:23:39 I face and shape the back of the gear blank
0:25:15 I turn a stronger mandrel
0:27:43 I adjust the lathe to thin down the gear blank
0:34:22 I turn the gear blank to the correct thickness
0:37:55 I adjust the lathe for turning the outer diameter
0:43:28 I remove a lot of material from the outer diameter
0:45:43 I turn the outer diameter of the gear blank to the correct size
0:52:49 I mill the tooth positions on the gear blank with a felt-tip pen
0:59:41 I mill the gaps between the gear teeth out of the gear blank
1:02:26 I'm evaluating the gear I made
1:03:38 I attach the gear to the four-jaw chuck of the lathe
1:05:37 I'm facing the front side of the gear
1:07:18 I start boring the center hole
1:09:13 I bore the hole near the right size
1:10:56 I bore the hole to the correct size
1:12:53 I bore a recess for ball bearing
1:16:36 I evaluate the recess I made
1:18:48 I adjust the milling machine for milling the cover plate
1:21:40 I break a cheap Chinese endmill
1:23:32 I change to a better but bigger endmill
1:26:37 I mill the side parts of the inner hole of the cover plate
1:29:01 I mill the curved parts of the inner hole of the cover plate
1:30:57 I drill the bolt circle of the cover plate
1:32:17 I chamfer the three bolt circle holes
1:33:22 I drill and tap M4 threads on the gear
1:38:08 I drill pin holes in the gear
1:40:15 Final words
1:41:46 End credits
The video is spoken in German but it has good quality hand written subtitles in English, German and Finnish.

[@HuibHoogendoorn]

Esko, Die probe verteilung mit den Stift ist genial. Danke dafur.

[@lul9670]

Vielen Dank für deine immer sehr detaillierten Videos. Man kann damit immer wieder neue Dinge fürs eigene Hobby lernen.

[@jst.hilaire354]

You're not the first person to screw up a gear cutting job. lol. I wonder a little at why you adjust backlash when you are indexing though. It looks a little like a backlash error. I usually just set the binder a little and index against the binder. Always on the same side, the head drives the backlash all the way around. Slipping on the mandrel is unfortunate. Love your channel.

[@1crazypj]

Module (metric) cutters run the opposite direction to Imperial cutters so Chinese didn't get it backwards.
I posted the same on 'This Old Tony' a year or more ago

[@FinnoUgricMachining]

Whichever is the "correct" direction. Anyway, it is good to know that these cutters may have that kind of a difference. One could easily end up buying the wrong cutter because of this. I always buy the whole set of 8. Some cutters have their teeth range printed on them, sadly, not all.

[@1crazypj]

@@FinnoUgricMachining I don't think it's common knowledge that metric/module cutters run opposite to DP/inch type cutters but as there are so many people cutting gears on You Tube I can't help commenting when someone didn't know. I was teaching at a trade school for 12 years and can't help myself 😁