Betsy, Travis
MC3
Today, we removed the dummy mass from the suspension and installed the glass IMCF06 optic. We immediately found that it suffered from a pretty good pitch error. This is likely due to one of the 2 newly introduced factors: the new wire loop has a length error or the prism is in slightly the wrong place. Tomorrow we will try switching the wire loop.
MC1
We rechecked the height of the optic in this supension and confirmed that the top of the barrel is sitting at 213.6mm from the table surface. The spec is 215mm +/-1mm. Tommorrow we will try a few adjustments to bring the height into tolerance. On a side note, Travis looked up the dummy mass diameter and compared it to the glass diameter. Both substrate drawings callout a +/-1mm tolerance on the diameter of the mass, but the optic measures to be at +0.8mm from the spec, using most of the tolerance and possibly leading to the height mismatch between the metal build and this optic build.
Travis was able to recover some height on MC1 via using the slop in the holes which mount the wire loop clamps. The optic is now sitting at 214.1mm which is within the 215 +/- 1mm spec.
This morning, we poked around and determined that because this optic has a diameter larger than the metal (specifically 150.85mm), the center of the optic would have been at 154.4mm from the table surface when installed in HAM2 on it's 15.8mm spacer. Luke reports that the nominal centerline position of the MC1 and MC3 mirrors from the table surface is 155.8mm. So we removed one D1200043 (s/n 113) weight from the top of the top mass - the height is now 214.7mm (top of optic barrel to the table surface). With the removed weight, the MC1 centerline will now be at 155.0mm.