Today, the course pitch adjusters on the top stage of the main chain were adjusted (very iterative). After a few rounds of fine adjustments, the pitch of the ITMy was set to under 1 mRAD. We proceeded to bring the lower reaction chain in to mate. We pulled the FirstContact from the CP HR and cleaned off leftover particulate with swaps and the N2 gun. I had to do an acetone wipe around the entire edge of where the FC was, in 1" from the ID of the gold coating. I also had to do a spot acetone cleaning on a smudge at 6 o'clock about 2" in from the hold coating.not sure why the apparent FC smudge didn't come off with the sheet. Then, we pulled the FC off of the ITMy AR. We observed a streak almost centered on the AR surface likely from the FC. Maybe the FC was too thin here, although the sheet did not break in this location. This streak is too central on the mass, so unfortunately we will have to reapply another sheeyt, let it dry, and pull it in hopes it picks up the smudge. We had to abort mating the reaction chain until this is finished and the AR surface is clean. Note, we still observe particulate on the masses, even after N2 blowing.
Some details and numbers regarding the pitch adjustments done yesterday.
Before the fine adjustments the quad hang pitch was measured:
The resultant pitch change for one CCW turn on each pitch adjuster was approximately 436 urad down.