I finished grinding the primary and I'll work on other fronts now to give Logan a chance to catch up.
Meanwhile I also made a silicon rubber mould for making the numerous polishing laps needed for the corrector lenses. Small polishing laps are a pain to make without such an aide.
I used plain hardware store silicon rubber that I pumped into the improvised Teflon mould. It would have taken months for the silicone to set all the way through, but I did not have the patience and opened the mould after two weeks. As a result the underside is a bit rough, but the top side squares are smooth and well formed. I haven't used it yet, as the lenses are still at the rough grinding stage.