Comments by "Keit Hammleter" (@keithammleter3824) on "This Old Man is Expert in Making Spur Gear From Old Ships High Strength Sheet" video.

Now I've seen just about everything bad. What a dopey time-wasting inaccurate way to mount the gear blanks for milling! If you can't make a mandrel of correct diameter for the job, shim the shaft you have with cooking foil or even paper. That takes only a minute or 2 and then the gear is accurately centred. Hear that hum during turning the blanks? That's tool chattering due to an incorrectly ground tool, and/or wrong speed, or possibly a ruined spindle bearing. It should be corrected immediately. The interesting thing is - the operator seems to know he's doing something wrong, but can't figure out what, or is just lazy and carries on anyway. The milling cutter is cutting on only some teeth - you can hear it. Not surprising if they "sharpen" them by freehand grinding, but it may be the mandrel is bent. You can see the blank rocking as the teeth are cut - not surprising given the way they treat their tools. The old man seems to have little to do with it, other than displaying the finished product and cleaning the swarf out of the job. Perhaps he's someone's grandfather who has been found a job.
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