Reports until 19:11, Tuesday 28 October 2014
H1 ISC (IOO)
kiwamu.izumi@LIGO.ORG - posted 19:11, Tuesday 28 October 2014 - last comment - 12:01, Thursday 30 October 2014(14690)
peek at PR2 baffle

Alexa, Kiwamu,

In response to Keita's alog about the PR2 baffle, we took a peek at the PR2 baffle by opening some of the viewports on HAM3 and HAM2 spool.

Conclusions:

 

(PR2 baffle check out)

We opened up a viewport on the East side of HAM3 which the leftmost one with an illuminator attached on. This was the only available viewport to open up. We removed the illuminator and looked at the baffle through the viewport. We confirmed that there was no cross bar structure on the side of the baffle unit as shown in the DCC document (D1000328). We could not see the top part of the baffle where it supposed to have a cross bar structure. We took some pictures and I attach them to this entry.

(Peek at the aperture position)

Then we tried a different zooming in the PR2 digital camera in order to have a better view so that we can determine if the aperture hole is in the middle of the baffle unit or not. With a help of flash light illuminating the PR2 baffle from the HAM2 East side viewport, we could clearly see the edge on both right and left sides of the unit as well as the edge of the aperture. It looked like the hole is centered with respect to the right and left edges of the unit. We took several pictures of it via the digital camera so that one can evaluate the position later if necessary.

(MC2 scraper baffle check out)

Then we opened up another viewport on the West side of HAM3 in order to see both MC2 and PR2 baffles. Though, the MC2 baffle was completely occulting the PR2 baffle and therefore we could not see it. We could still confirm that the MC2 baffle has a cross bar structure on the side as shown in the design document (D1000327).

Images attached to this report
Comments related to this report
sheila.dwyer@LIGO.ORG - 08:54, Wednesday 29 October 2014 (14699)

The baffle hole seems to be centered in the baffle frame within 3mm from the picture. Good.

The distance from the left baffle hole edge to the left inner edge of the baffle frame is about 52 pixels, it's 56 pixels  for the right, i.e. about 2 pixels offset to the left, which corresponds to 2 or 3mm.

Keita

keita.kawabe@LIGO.ORG - 12:01, Thursday 30 October 2014 (14737)

The hole diameter is also good (i.e. the ratio of baffle frame width to the hole diameter on the picture reasonably agrees with the spec).

Switch between the first attachment and the second to see if you agree with my assessment of the edges.

  Nominal Image
Baffle diameter 2.756" 53px
Baffle height 8.34" 160px
Baffle width 8.74" 165px
Diam/Width 0.315 0.321
Height/Width 0.954 0.970
Center offset none 2px to the left ~ 3mm
Images attached to this comment