Reports until 09:40, Wednesday 25 August 2021
H1 SQZ (VE)
camilla.compton@LIGO.ORG - posted 09:40, Wednesday 25 August 2021 - last comment - 12:16, Wednesday 02 April 2025(59714)
Rough Balancing of OPOS Complete

TJ and I completed a rough balance of the VOPO platform in the optics lab.

Done without cables as they and mounting hardware are not yet ready. We struggled to get the H1,V1 side of the platform up high enough. Platform was floating with 25-75g mass on OPO lid but H1,V1 bottoms out with 125g.  We will have some play of where we route the cables on the OPO lid which can help us. Attached are photos of the vertical alignment at the 3 blade posts, 1 and 2 were centered, 3 was a very little low.

Shown in photo 1 bottom we used: lateral masses: D1500421-v3 s/n1; D1900503; small weights: qty2 D1500480-v2 300g; D1500479-v2 500g; D060359 100g;
Shown in photo 1  right side we used: qty2 D060359 100g; lateral mass D1500419-v4 s/n2; D060359 25g; Dog clamp;
Shown in photo 2 we used: D1500480-v2 300g.
 
We will discuss with the SQZ team if we are happy the the dog clamp as a cantilever will not create any strange modes.
We used part D1900503 which doesn't have the smoothest finish but comparing to the roughness gauge (photos of top and side) we think will be okay, it is smother than 250P. Tagging VAC  for thier opinion.
Images attached to this report
Comments related to this report
chandra.romel@LIGO.ORG - 11:22, Wednesday 25 August 2021 (59717)

Not ideal given the roughness adds surface area, but given these parts passed C&B RGA scans, we'll allow this one-time exception.

camilla.compton@LIGO.ORG - 12:16, Wednesday 02 April 2025 (83703)SUS

This was not updated in ISC, ASSY-D1500295-D1500295-H1, I have now removed D1500420, D1500422, D1500423, D1500479 x1, D1500480 x2,  and added D1500419-v4 02, D1500421-v3 s/n1, D1900503-v1 005 to the record. The D060359 parts are bulk so not updated, more were added when balancing in chamber 59939