This is a small sub part of finishing off my camera boom, but rather than bury this in that video, I thought I'd break it out into a separate clip as it may be easier to reference for those just interested in it.
I've done it, and successfully, but it needs care with heating the steel blank - too hot and the plastic melts out, too cold and it does not form the teeth. If you have an IR contactless thermometer, that could be a great help.
That's a horizontal milling cutter that has a 90 degree grind on it. If I were using it to mill a flat piece it would put a 90 degree groove in it. I think it came from a box of stuff someone gave me, but eBay could be your friend...
Do you know the formula based on the diameter and the number of teeth to determine the angle of offset required. I know it's possible to cheat with cad but I'm not familiar with cad software. Thanks.
It takes a bit of geometric thinking, but I work out the circumference of the part and divide by the number of teeth. Because it is a 90 degree tooth, the mid-plane distance between teeth is twice the distance from the mid plane to the bottom of the tooth gullet (or a tooth tip). Knowing that mid plane to bottom gullet distance and the radius, angle= arctan(tooth gullet distance/radius).
I've seen articles showing these used back-to-back with different pitches to give a low profile discrete movement rotary table. For example, coarse movement one way then fine movement either forward or backwards gives many more discrete movements.
