There are plenty of options out there for readymade templates to trace designs on metal clay, polymer clay, or sheet metal. But if you draw your own design on paper, it doesn’t last through many tracings before getting flimsy.
One option is to cut apart an aluminum soda can, and flatten it out. Then trace the design on the unpainted side and cut it out with scissors. Voila! You now have a long lasting template of your own design.
I made most of my templates for use with sheet metal, before I started using precious metal clay. While aluminum can react badly with PMC, I have never had any trouble with the soda can templates. I think it’s because the paint on the outside and the thin plastic coating on the inside keep the aluminum from coming in contact with the metal clay.
Top 2 figures: An aluminum template and a brass pin with silver eye.
Bottom 3 figures: A drawing of a tuna on paper, the aluminum tuna template, and the tuna cut from a piece of 20 gauge sterling sheet.
The little brass pin is one of my oldest templates, while some of the templates in the foreground of the 2nd and 3rd photo are the most recent, used with PMC.