It is now full steam ahead for the mirror. We are in the final polish round and working on taking material out of the center to make it deeper. In small mirrors this can be done in a few hours but with a 1.1 meter we are looking at about 100 hours.
The mirror was lifted from the grinding machine for the first time in 5 years and flipped. We bored a 10" diameter hole in the back using a stainless cooking pot and abrasive. The cut was made 80% of the way through the mirror to relieve stress before final figure.
Here we are using the 6" tool to work down the edge.
We are now well over 200 hours into the final polish.
Problems with hard pitch dug a groove near the edge
and we are spending most of the time working down
the rest of the mirror. The polishing will stop for
the summer but we will resume full speed this fall.
The mirror has to be finished by the end of the year
because the project is moving to Arizona.