BS suspension mirror has been changed

From yesterday afternoon we tried to remove the dummy mass on the BS suspension and change the real mirror.

Yesterday afternoon we tried to lower the inter-medium mass first, but we round out one of the top four screw is very hard to loose(pic 1), so we tried to lower the mass with one of the picomotor. But only with the picomotor the wire was not loose enough to remove the mirror, so finally we managed to turn that screw, and today when we need to fasten it, we changed to another screw.

So today we tried to put the real mirror on the wire, the stand-off and the magnet are all stick well, but since the real mirror is a little bit smaller, the white stopper on the up side of the mirror can not help a lot. Also when we try to put some intense on the wire to lift if from the stoppers, the mirror tilt a lot, so we turn the pitch picomotor to make it more or less vertical.

Then we tried with picomotor to align the beam again, while we were trying we found out the yaw picomotor of BS suspension does not work, we checked a bit, for now we can only say it is not the problem of the driver.We will try to fix this problem tomorrow morning. Then we tried to align with move the picomotor by hand, so we did align the beam, but maybe because the quality of mirror becomes higher, there are too many reflection everywhere, so the beam on the 290m target looks much worse than before.(pic 2)

The other thing is that we checked the picomotor driver for the end room yesterday and also checked again today, it works well both the top layer and the port layer. Now we have enough drivers.