Steampunk Protostar #13 - Designing The Pod Ends

In the spirit of adhering to the KISS principle (Keep It Simple, Stupid), I have opted to make the rear pod pieces in an easy-to-turn hemispherical shape with a short glue base.

The initial step of this process is, of course, ascertaining the necessary dimensions for the parts by measuring the base of one of the plastic pods.   A digital caliper helps greatly here.

Outside diameter:

Inside diameter:










Next step is to break out the drafting board and tools in order to lay out the full-size template on a piece of manila folder stock.  This template will be used at the lathe during turning to constantly monitor progress on correct part shaping.

Once the template is drawn, I carefully cut it in half along the centerline using a straightedge and  a sharp X-Acto blade

 I carefully cut out the curvature of the part, following the line precisely.

Again, using a straightedge, the cut is extended straight back along the line defining the outside diameter.  Note that I am not cutting out a line for the inside diameter that marks the base.  Doing so would not allow the template to rest evenly on the balsa stock during turning.

Also note that the template is only marked for the locations of the part's base and rear cut-off line. Once the part is correctly shaped on the lathe, these marks will be transferred to the stock as reference for those additional operations.  I'm going for a 6mm base length, as this should be adequate for gluing into the plastic pod.

The template is now cut out and ready for use.