The dividing head sits on the bed of the Sherline mill. Often in the work I do there is a need to turn a small fitting from bar stock in the lathe, move it to the mill to cut some flats or slots or make a cross-drilling, then return it to the lathe for finishing. The dividing head takes the same collets and chucks as the Sherline lathe, and that makes it very easy to move the parts from one machine to the other without losing the centre or otherwise upsetting the work. The dividing head is based on a standard Sherline headstock. It may seem somewhat lavish to spend money on a headstock with high-speed precision bearings that are not required, but it was an easy way to the tool I needed, and ensures that it is completely compatible with all the other Sherline accessories.
First it was necessary to modify the headstock so that it could be mounted on the bed of the mill. Here it is set upside down on the mill, and held to an angle plate by the screw holes for the motot bracket. The additional metal on the base that is not required is being machined away. A slot was subsequently cut around the base with a slitting saw so that the dividing head could be secured to the mill table using standard Sherline clamps. Note the sticky tape to keep swarf away from where it should not be.
The new components are (a) an index plate, and (b) a spring-loaded plunger on a bracket that locates in the holes in the index plate. The index plate goes where the pulley is usually located, where there is a flat on the shaft to secure it. There is an index plate available from
Carter Tools that provides 40, 50, and 60 holes. It needs a hub making to fit it, but that is a fairly simple turning job. Since I needed other divisions as well, I made another plate with 36 holes (and room for other hole numbers, should I need them), using a lashed-up arrangement involving a change wheel on the Myford lathe to get the divisions. I would not generally recommend it so I won't describe it here, but you can get the general idea from
The Amateur's Lathe (L. H. Sparey, Special Interest Model Books Ltd., 2005).
The photos below show the assembled head with the Carter Tools plate, and my own 36-hole plate.
Download drawings of the dividing head and index plate blank here.
See the dividing head in action here.