Hobbing a Brass or Aluminium Drive Pulley to Stop Belt Slippage

I've posted up photos before of hobbed pulley drives. It's a process that works very well and gives a professional result (very similar to what Wilesco does on their drive pulleys). I've done well over a hundred brass and aluminium drive pulleys now.

Here's a vid I did a few years ago of the process -

Some pics of pulleys I have hobbed

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