What sort of gears are used in ratchet mechanisms? I am looking at an auto-traverse gear on a Boxford shaper, which is missing a couple of teeth. I would like to make a new one.
It does not appear to be of an involute form, having teeth that seem 'square' rather than 'curved'. Would it be more closely related to a splined shaft than a gear wheel?
Because it must engage the ratchet plunger (i.e. not a pawl) in both directions - for bi-directional traverse - the gear is symetrical, with opposing tooth flanks identical.
Any thoughts? Do I need a special spline cutter, or would a mill with a horizontal 4th axis be sufficient?
Thanks for any tips.