As the topic says I consider making a mirror on these principles
Glass: Plate glass 19mm thick (the thickest than can be found locally)
Tool: tile on plaster tool
Carborundum 80, 220, 400, 600
(the old books say that grinding can be finished with 600 so why not? few abrasives for
economy and lower possibility of contamination, plate glass grinds really fast especially with
carborundum which is very hard)
80 and 220 can be purchased very cheaply or even be given for free as they are used for sandblasting
by the ton, 400 and 600 can be purchased by gemstone polishing supplies stores.
Initial fast polishing with HCF (honeycomb foundation) lap, finishing with pitch (mixture of beeswax and pine rosin)
and rouge (very cheap from house construction supplies, has to be "washed" though by precipitation).
Foucault tester: no micrometers, no springs to take up slack only the old tried method by Rev. Ellison
of marking with a pencil the knife edge positions and reading the pencil marks with a fine scale and magnifying
glass. It can be made slitless though I guess.
The mirror will be 8" f/7-9, diagonal will be either purchased or cut rectangular from regular
Any thoughts by experienced mirror makers?
Thank you in advance!
Edited by Giorgos, 15 October 2019 - 12:25 AM.