I am in the process of prototyping a fusee dial clock which has a tide dial incorporated. Having worked on my train counts for the movement, I found that one of the wheels I needed to cut for the motion work contained 149 teeth! Those who have worked on cutting gear or wheel cutting will know this is going to present a significant challenge with a traditional dividing head.

This was going to need a little careful thought to be able to achieve this. My dividing head which I use for rotating wheel blanks by the precise division for cutting teeth uses dividing plates for helping you to divide by typical divisions. This allows me to easily cut wheels with 30, 60, 90, 96 or 144 teeth for example.
The solution I came up with was to attached a stepper motor to my dividing head controlled by a Raspberry Pi! Bresenham’s line drawing drawing algorithm was also put to use for averaging out the unequal steps needed for the divisions.

For anyone interested in the details of this project, it was published as an article in the BHI’s Horological Journal. I have also published technical details for the Raspberry Pi project in github. I have also provided a link to the article in pdf format.
