Ordered some laboratory hourglasses. They are 1.7-1.8mm thick.
Just finished the domed glass for the Roskopf from one of them. The final diameter is 40.05mm. First, 45-46 mm middle was cut.
Here is the finished crystal, the old plastic one, the front bezel and the tools i used. Desired diameter was reached with the diamond disc. 1000 Grit sandpaper, 3000 grit and finally 10000 grit diamond paste was used on the edge.
Perfect heat-fitting. No fancy cement or glue However, i added some diluted UV glue on the edges after fitting to make sure it wont fall off. It will cure tomorrow on the sun Now i am waiting for the thin flat glass for the back bezel.