Quote Originally Posted by Voicecoil View Post
Mmmm, tricky one as ideally you want the angle of the teeth to increase as you move outwards. If you're cutting with a constant angle cutter would turning each surface to a slightly concave conical section sort the problem I wonder? That way the angle of the teeth is constant but they become wider as you go outwards. Sorry, I don't have any 3D CAD here at home to check it out. Alternatively cutting them as a square (or trapezoidal) section with the width increasing radially outwards would do (2 passes for each cut offset by 1/2 the angle) might sort it, but engagement would be more clunky than with triangular teeth.

It’s tricky to get your head around, I had to mock it up in CAD before I understood it properly.
Apart from the apex of the cut at the bottom of the teeth all the other faces and angles are falling away from each other.

The easiest way to think of it is that all faces and corners are formed by the two cut faces meeting and the cutting tool paths draw closer to each other as they come closer to the centre.

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I’m not sure I even understand the geometry of mating radial teeth but I’m feeling that it’ll probably need to be a CNC path. I hope not but...