October 2022 Segmented Rings for Bowls

Steps for making a segments bowl

1. Make a plan.  Draw the cross section of your bowl out on graph paper.  This will help determine the outside diameter of each ring.  You will need to know the height of each ring – they do not need to all be the same height but it might be easier at first if they are.  You will need to determine the outside diameter of each ring and the ring thickness of each ring.  You will also need to know how many segments each ring will have.  (I will use 16 for this demonstration but any number greater than 5 can be used.)o)
2. Use a segment calculator – like http://woodturnersresource.com.  Enter these numbers:
   1. Number of sides:  ie. 16
   2. Outside diameter: ie 8 (units are irrelevant but I doubt that you want an 8mm ring.)
   3. Ring thickness: ie 0.5 (for a ½ inch thick bowl)
   4. “Fudge factor”: ie 0.25
   5. Select “Calculate!”
3. You will be given the following measurements:
   1. Outside Segment Length:  ie 1.691
   2. Inside Segment Length: ie 1.268
   3. Segment Thickness:  ie 1.062
   4. Cut Angle:  ie 11.25
4. Once you have these measurements, it is time to mill your sticks for the segments.  The height of the stick will be the height of the ring.  The thickness(width) of the stick will be the Segment Thickness given above.  The length of the stick will be at least the number of segments (16) times the outside segment length (1.691) –  (27.056) – plus enough extra to safely use the sled.
5. Mark the stick with a sharpie or other marking pencil.  These markings will either be hidden in the joints or turned away at the lathe.
6. Trim one end of the stick to the cut angle using the Wedgie Sled.  
7. Cut the rest of the segments – plus a couple extra segments – using the Wedgie Sled.
8. Dry fit the ring remembering to flip every other segment (actually a trapezoidal prism) so that every other segment has a curly mark facing up.
9. Once you have the ring as desired, apply glue and clamp the ring using the clamping method of your choice.
10. Once the glue has cured, sand the rings flat either by hand on a flat sanding surface or with a drum sander.  (Be sure to take VARY shallow passes with the drum sander.  These joints are end joint glue ups with no added support and are not very stable.  Stability will be greatly increased when gluing the rings together in a “stairstep” arrangement that will allow long grain to long grain glue joints between rings.
11. Complete the bottom (solid) “ring” and glue the rings together.
12. Decide how you want to attach to the lathe and have fun.