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Reports until 16:12, Wednesday 19 January 2011
X1 SUS
travis.sadecki@LIGO.ORG - posted 16:12, Wednesday 19 January 2011 (492)
BS/FM (FM1) first full hang
Today I successfully fully hung the BS/FM (FM1) for the first time.  After several rebuilds of the wire loop/middle wire assembly due to kinks and breakage (2 more rebuilds today after Betsy's last post), a complete hang and rough adjustment was completed.  After setting the blade tip positions in the top mass, I released it and the top stage from their stops.  The initial pitch of the top mass was out ~10 degrees, during which time I noticed that due to the off-center position in which the wire exits through the base plate of the top mass (see pic 6), the wires were touching the edge of the base plate holes.  This is something to watch carefully for in subsequent assemblies as a more severe pitch issue could damage the wire assemblies enough to warrant a rebuild.  I would recommend slowly lowering the EQ stops until it becomes apparent that this is not an issue.  If it seems to be, stop and reclamp the mass until enough mass is shifted to hang level.  It did not seem that the contact was severe enough to gouge or bend the wires, so I proceeded to move addable masses around on the top mass, as it became apparent that that the pitch adjuster screw would not have enough range to remove all the mis-pitch.  In all, I had to move ~200 grams of masses to the OSEM side of the mass.  Having done that, all the DOFs look rather good.  However, the chain does appear to be hanging biased toward one side of the structure, so I will have a look at centering it up using the top stage adjustment tomorrow.  
Images attached to this report
Displaying report 1-1 of 1.