by Betsy:

The ETMx QUAD is suspended in the staging building on the test stand, again.  Major retrofits were installed over the last week.  The reaction chain cabling, including ESD, has been laced.  We are tuning it with metal dummy masses which match the weight of the glass masses in prep for moving it to Ex, install/weld the monolithic glass/fibers, and assemble it on the cartridge.  The masses have been tuned in height:  the reaction ERM dummy currently sits 0.5mm higher than nominal, the test mass dummy is at 0.25mm lower than nominal - the tolerance is +/- 1mm.  This is about as good as we can do in metal given the errors in the weight matching.  Roll and relative side-shift between the chains is also within ~1mm.  Adjustments to the table cloth were made and all 12 top and 4 UIM BOSEMs appear to line up.  There doesn't seem to be anyone home on the test stand QUAD medm so after some maintenance on X1SUSQUAD we'll hook up the BOSEMs for testing.

Weigh estimates were calculated from the vendor-measured ETMx optic.  Weights set are as follows and are inclusive of prisms/ears/etc on each mass:

PUM glass 39,600g

ETM08 glass 39,647g

PenRe metal mass 52,962g

ERM02 glass 26,145g