How Would I Machine this CAD designed Ratchet

[peter1972Participant @peter1972]

Consider cutting the teeth with a 45° single-angle milling cutter, initially without the cylindrical inner: that can be added later if needed!  For the drawing below showing just the first cut, I have assumed 50mm diameter and 26 teeth.

The aim is to angle the workpiece on the milling table so the depth of cut reduces to zero at the centre of the workpiece but gives the desired angle for each tooth.

The angle at the centre is 360°/26, which gives the dimensions of a right-angled triangle as shown.

At point ‘A’ the depth of cut needs to be 5.98mm if using a 45° cutter. By my calculations, that means the workpiece needs to be angled on the milling table by about 14.3°.

The above should produce sharp teeth with no flat tops: not quite as shown in the opening post. Adjustments could be made to the geometry to give flat tops.

 

[Nigel Graham 2Participant @nigelgraham2]

The above should produce sharp teeth with no flat tops: not quite as shown in the opening post. Adjustments could be made to the geometry to give flat tops.

Or more simply, cut the teeth slightly deep then gently skim the sharp crests off?

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