My Job, Part 3: My Job.

Currently I hop out of bed at 4 AM, trying not to waken Twila (impossible, but hopefully she falls quickly back to sleep), get dressed in the living room, pour a thermos of juice, and go to the lab. There I remove the hardware from the optics. The hardware is:

--- Load bars - they press the strongbacks against the optic.

--- Strongbacks - they hold the graphite spacers.

--- Guide wheels - they are on each end of the optic and have slots that the strongbacks and load bars slide into.

After I remove that crap, I check the settings on the computers, possibly adjusting them based on measurements from the day before, and then initiate 3 grinds, each of which takes 1 hour. Rough Grind 1 takes off a lot of spacer, Rough Grind 2 takes off a bit less, and Final Grind just a smidgen. During the grinds I have to pay attention to the sounds the grinds are making, as well as a couple of gauges.

At the same time, I am preparing the strongbacks for the next day. Simply, a strongback is a bar the length of the optic with a groove in it. Teflon tape is placed on the bar, covering the groove, and then a spacer is inserted into the groove. The tape prevents epoxy from getting on the strongback.

When the grinds are finished, two techs clean and inspect the optics, running precision scans to ensure that the spacers were ground to the correct height. Then they epoxy the mirror segments and new spacers (in the strongbacks) to the optic and press that all together with the the load bars. It takes several hours for the epoxy to harden. The next morning I magically appear and the process repeats.

Currently one optic is at Layer 27 and the other is at Layer 13. At about Layer 65 the number of mirror segments doubles, as does the work on that optic. I have to get the 3 grinds done before the techs arrive, but usually I finish a bit early now, so I probably won't have to go in earlier when the first optic changes. All of us are a bit anxious about the last stage, though, when both optics will have 120, rather than 60, sets of load bars and strongbacks. Probably I'll have to get up early.