[LargeFormat] a gritty day

[philip.lambert]

I was advised by a helpful member to make my own ground glass by grinding
ordinary glass with 600 grit and a little water. Eventually some total
stranger gave me some grit and I bought some cheap 2mm 6inch glass squares
today and have successfully made finely ground glass. A thin, watery slurry
works well.
Regretfully the cheap glass cutter I bought doesn't work so I will ask the
man in the glass shop to cut one 6inch square into two focussing screens for
my Miniature Speed and Century Graphic.  I nearly bought some expensive
Sinar glass screen from Mr Cad (it's an option still open) but hopefully my
own product will work.
Does anybody know how to make my own fresnel screen?  PL