Yesterday afternoon, I went back into the BS chamber, and flipped both PR3 and SR3. Now all of the recycling cavity folding mirrors have been flipped.
For PR3, I followed the same procedure as SR2, setting a reference position, removing the optic, flipping it, etc. When I put it back in, I realized that since this has a 41 degree angle of incidence, the beam going to the BS had translated north by ~1cm. After some fiddling, Koji pointed out that the 2 degree wedge probably had a more significant effect than just the HR surface having moved back a small amount. Anyhow, we adjusted PR3 such that we were going through the BS aperture, as well as the ITMY aperture.
During the flip of PR3, Annalisa and I noticed that the arrow on the barrel of the LaserOptik mirrors also indicates the thickest part of the wedge. This is opposite of our SOS optics, where the arrow's position on the barrel indicates the thinnest part of the wedge. For both PR3 and SR3, I kept the arrow on the same side of the optic as it was originally.
I then flipped SR3, following again the same procedure. PR3 I had done a tiny bit of pitch rebalancing, although I think it was unneccessary, since it is within what we can do with the poking/hysterisis method. SR3 I did not do any pitch rebalancing. With PR3 aligned at least to the ITM, Koji and I aligned SR3 and SR2 so that the AS beam was hitting the center of all the SRC optics. We also adjusted the steering mirrors after the SRM to get the beam centered on PZT3, the last optic on the BS table, which launches the beam over to the OMC chamber. We scanned around a bit by turning the PZT's knobs, but we were unable to see the AS beam on the camera.
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