Segmented Turning by WDK™

Segmented Turning™ - Clamping Ideas


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Designing a Segmented ProjectDesigning a Project

Translating the Design into Cutting InstructionsTranslating the Design into Cutting Instructions

Cutting SegmentsCutting Segments

Gluing and Clamping RingsGluing and Clamping Rings

Flattening Segmented RingsFlattening Rings

Gluing up the Segmented ProjectGluing up the Project

When you glue up your first ring; how to clamp it will be a big question. If the ring is relatively small, say 6” or less, a stainless steel hose clamp does a good job. You can get it really tight and they don’t cost too much. You can also use several large rubber bands for rings up to 10". If the ring is much larger than that, the hose clamp or rubber band idea kind of goes south unless you have multiple hose clamps. You can join two stainless steel clamps together to accommodate a larger diameter ring. Two clamps unite to become a larger one

For larger rings, I resort to a really simple clamping mechanism borrowed from the tourniquet. Just take a couple of strands of sturdy string/twine and make a loose loop around the ring. Then find something to use as a twister. I use clothespins. Depending on how strong the string/twine is, you can actually clamp with as much force as with the hose clamp. Once you’ve twisted it up tight, use a clamp or a weight to keep it from coming loose while the glue dries.

ring clamp for segmented ring glue-up

If you take care to match up the corners at each segment joint, the combination of the uniform forces of the tourniquet clamp and accurately cut segments will result in a perfectly round ring.


When the clamp starts to draw tight, a hammer becomes a good tool to try to coerce the segments to lie flat. Just give a whack to each and every segment while holding the ring down in a flat surface. You’ll need to go around the ring three or four times.


If you are gluing up a ring that is made up of a sandwich, you'll want to pay particular attention to getting the ring as flat as possible so that your sandwich layers will not jump up/down as you go around the ring. In this situation, you will want a ring press. You can construct one simply by using 1.5" galvanized pipe and a built-up, very rigid, wood base. Take 4 equal length pieces of pipe and put a 90 degree elbow on one end and wall mount rings on the other end for fastening to the wood base. The length of the 4 pieces determines the maximum height you can clamp because you can use this press for project glue-up as well. Then add 4 equal length pieces to the elbow ends and screw these into a 4-way connector. The length of these 4 pieces governs the maximum diameter you can clamp. Now, the expensive part, drill and tap the center of the 4-way connector to accept 3/4" x 10 tpi all-thread. Attach some kind of turning device to the top of the all-thread and make yourself several cauls to use on the bottom end of the all-thread to distribute the pressure onto your ring/project. You'll only need to leave a ring in the press for a half hour or so and then you can move on to the next ring. I had a lot of wobble in my all-thread so I used JB Weld to attach a nut to the top and bottom of the 4-way connector to stabilize it. Ring Press for Segmented Project to Layer Glue-up

When clamping solid rings (the segment’s long side is the same as the radius) be prepared for trouble no matter how accurately the segments are cut. The culprit is moisture from the glue, which causes the tips to expand. There are five ways I know to limit the effect:

  • Clamp tighter; but you’re working against an irresistible force
  • Get all the segments glued and into the clamp as quickly as possible before the water can do its thing
  • Try using a glue that isn't water based
  • Glue only one or two joints at a time; taking care to keep excess glue away from the joints not yet being glued
  • Forget the whole thing and use a plug in the middle of a wide ring

A glued up ring can be somewhat tender. I have yet to break one in normal handling and flattening, but dropping one on the floor is another story. A thin ring with the grain running around the circumference will be the weakest because all of the joints will be end grain and glue starved.



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Page Last Updated: 9/5/2014