5 segment wedgie for woodturning

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A question for future reference. Sometimes ideas must gestate in my head, others can't be held back. This one is not even close to a gleam in my eyes.

It looks like segmented rings are all even numbered. If I want a 5 segment ring, do I double, or halve a 10 segment ring degrees? Or, some other method that looks like an Einstein theory on the blackboard.

I took general math all through high school, and use a calculator for all my timeses and guzzintas.

Don't ask why. But it could be cool.

Hey, you don't know me, but you don't like me ... Buck Owens

You calculate the interior angle of any equal sided polygon by subtracting 2 from the number of sides and multiply by 180 and then divide that by the number of sides.  For a pentagon:
((5-2)*180)/5 = 108°.
Divide that by 2 to get the miter angle for cutting each side : 54°.

I suspect that most segmented rings are  even simply for symmetric.  Note that the fewer corners, the wider the pieces you make the segments from need to be (or the narrower the maximum ring can be once turned). 

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

It occurred to me that another reason besides symmetry that you don't see many odd number segmented rings may be because some of them wind up being weird angles that are difficult to set with protractors or miter gauges.  For example, with 7 sides the miter angle would be 64.285714285714...° and 11 sides would be 73.636363... .  Not exactly easy to set with traditional measure devices.  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

Another alternative may be a Mitre Set,

It may be a tad cheaper than a course in SketchUp or a uni degree.

No, I'm bot a segmented turner... I just love gadgets.

If your first cut is too short... Take the second cut from the longer end... LBD

You guys are good !  Nathan, I could read it all day and never get it. I'm glad you did. I should be able to dial in 54 degrees on the Incra. Thanks! 

LBD   I like it!  Like you, I believe in total redundance in gadgetry. 

Hey, you don't know me, but you don't like me ... Buck Owens