Primary Mirror Assembly

The Primary Mirror Assembly (illustrated at right) includes the mirror itself, the mirror housing, and the light shield. The mirror is a solid piece of Pyrex, and weighs about 400 pounds. The light shield is fitted through the hole in the center of the mirror and is bolted to the base of the housing.

First the light shield is unbolted from the housing.  A sturdy flange at the base of the shield supports the central portion of the mirror, allowing the two to be lifted together.

We place wooden blocks atop the housing, and set the mirror onto the blocks.  From here, we remove the flange from the base of the shield, and remove the shield from the mirror.

When the telescope was first constructed, a special compression ring bracket was fabricted for lifting the mirror.  We retrieve this bracket from storage, fit it around the mirror, hoist the mirror out of the building, and place it into its foam-lined storage crate.