Bangle (bracelet) Mandrel

Pictured on this page is a custom mandrel I made with the help of some guys in work in the machine shop. The mandrel is for turning Bangles. I wanted a way to have the flexibility to change the orientation of the Bangle w.r.t. the axis of the lathe as many times as I wanted and in addition I wanted clearance to work on the piece from both sides at the same time. I did not come across any other Bangle making method that would allow for these requirements so I made it happen.

The mandrel itself is made from stainless steel. I started by cutting a cone into each end of the mandrel using a metal lathe. These cones will allow for the live center on the wood lathe to have a nice place to rest. I guess you could have also cut a simple blind hole into the ends, but I used a bit that actually cuts a cone to match the live center cone. Then I cut a channel along the mandrel to allow for the set screws that transfer torque (from the mandrel to the bushings to the Bangle) to have a place to grab onto. For this I used a HSS endmill. The two bushings (that hold the wood onto the Bangle and accept the set screws and the screws into the wood) I turned on the metal lathe. I first drilled out the center using a 1/4 inch and then a 1/2 inch drill. Then I turned the bushings down to size and parted them off. I clamped them together and drilled the hole pattern for the three screws that go through them into the wood on a vertical mill that has a digital read out that you can program a hole pattern into. The holes for the set screws we drilled on the vertical mill as well. Caution must be taken to ensure the two pieces stay aligned once the first hole is drill. If the pieces are allowed to move w.r.t. each other, the holes will no longer match up.