A form cutter a bit like a 1 sided involute gear cutter would probably do it if the centre section could be soldered into a ring so that the cutter could have run out room or have the centre recessed to just below the valley of the teeth

You would also have to watch that the cutter’s diameter was not too large otherwise it would hit the opposite side

We did have  asimilar thread about hole saws which need a similar sort of cut

If you could have a small radius in the internal corners then that opens up more possibilities

Is the boss in the centre of the ratchet necessary?  Because it is very difficult to machine into a blind hole that has a sharp corner.

I made a ratchet wheel for the lubricator on my engine by cutting teeth on a long piece of rod with a chamfer tool, then cutting a slice off the end for the ratchet. (lots of spare material for future projects).

Not sure [and I am certainly making no claim to fame] but I wonder if Jason was recalling the question I asked years ago about cutting a verge crown-wheel for a clock.

If so, it was never fully solved.

I will have a look for the old thread next time I wake-up in the middle of the night.

🙁

MichaelG.

.

Edit: __ ‘twas much easier to find than I anticipated:

https://www.model-engineer.co.uk/forums/topic/how-do-i-cut-a-verge-crown-escape-wheel/#post-212482

… still sipping a Glenmorangie

Edit: __ some of the content in that 2015 thread has gone awol so, for completeness I am quoting an observation I made in a related eMail:

Although JasonB and Mark C both provided very useful sketches … on close examination, both of them actually ‘demonstrate the problem’ rather than answering the question.

Mark was particularly helpful, and provided me with some more-detailed drawings; but the big ‘niggling’ question remained. [Zoom-in on a tooth in his SolidWorks rendering, and you will see that the tooth-tips are inappropriately shaped.]

The crown-wheel form would be the easiest, as the cutter runs right through the gullet and into the fresh air in the middle.

Alternatively, can the wheel be of more conventional form with the teeth cut across the disc thickness? (Shaped like a circular saw.)

Your original form is not an example of something being easy to generate in CAD but not make physically. You can do that in manual drawing too; and it seems quite a common mistake.