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2/16: Yesterday I started polishing a bundle of sci-fis that are cut to 0.907 inches. The screw holding the collar on the guide was on the left. With the micrometer I measured the space where we put the feeler gauges. It was about 0.09". I wanted to try bottoming out to the 0.025" feeler gauge. I twisted right in front at the polishing wheel and left in back away from the wheel.
2/16: Yesterday I started polishing a bundle of sci-fis that are cut to 0.907 inches. The screw holding the collar on the guide was on the left. With the micrometer I measured the space where we put the feeler gauges. It was about 0.09". I wanted to try bottoming out to the 0.025" feeler gauge. I twisted right in front at the polishing wheel and left in back away from the wheel.
2/19: Using the Carson camera, I identified which fibers are in each position in the bundle to be tested. Jim will show me tomorrow how to use the alignment collar for testing. I continued polishing the sci-fi bundle after identifying the fibers.
2/19: Using the Carson camera, I identified which fibers are in each position in the bundle to be tested. Jim will show me tomorrow how to use the alignment jig for testing. I continued polishing the sci-fi bundle after identifying the fibers.
2/20: Today I tried aligning the fibers for testing as Jim explained. I have not succeeded with that yet. I also continued polishing the same bundle of sci-fis.
2/21: I aligned the fibers in bundle 401 or 402 for testing (there is a contradiction between the ID collar and the strap color). There is one more problem, though. The fibers still seem prone to slide out of the Kapton straps. They might not stay in the right position on the popsicle stick as they are put in the dark box.
2/22: I put the fibers on the popsicle stick again. Yesterday I had them aligned but when I put them in the dark box they were bent differently and no longer aligned. I held up a measuring tape in the dark box and decided the horizontal distance between the popsicle stick end of the bundle and the top of the ramp is about 26 inches. Then I used a box on the conference room table to substitute for the top of the ramp and put the fibers in a position similar to what they assume in the dark box. I also had a stack of journals to hold the chimney end of the bundle in the bent position as it is in the dark box.
After some failed attempts, I aligned the fibers about right by holding them on the table in approximately the dark box position. Then I used the plexiglass stop plate to align them, but they were still not in the right position when I put them on the popsicle stick. I finished the alignment by pushing the fibers against the alignment jig while holding the slender part of the jig so it wouldn't break.
I put the fibers in the dark box and put them in the chimneys, but I may have bumped the laser while doing that, so the dark box might not work anymore. Somehow the curtain had fallen and I was trying to put the fibers in place with the curtain down. I had trouble finding the hole for the threaded rod on the popsicle stick too. From now on I will have to make sure the curtain is up before carrying the fibers to the dark box. I did raise it before taking the fibers out to bring them to the conference room. It must have fallen while I was working there.
2/23: I tried to run a fiber test, but the charts came up blank.
I continued polishing the sci-fis. I have some problems with measuring with the feeler gauges. It seems that while polishing there is less space for a feeler gauge than when the wheel is at rest. For example, with the 0.025" feeler gauge in place, the fibers don't touch the paper as the wheel is spinning. It's the same with the 0.024" gauge, but with 0.022" and 0.020", there is a little contact.
I was about to contrast this with the wheel at rest, but now I'm not so sure. I just found that at rest the 0.025" and 0.024" feeler gauges didn't fall down as I had seen earlier, but I had to press hard to keep them up. I will have to think some more about this.
But I think I will turn the sci-fis around again since it seems they are projecting more on the other side. This time the screw will be on the left.
Jim put the new part in the splicing unit and said I should check the pressures before fusing. I raised the pressure coming from the compressor and looked at the two regulators. I adjusted the right one that should be 95 PSI, but I could hardly turn the knob to adjust the left one that should be 57 PSI.
Before leaving, I drained the compressor at the bottom. There was not much rust this time.
I should have a to-do list for next week.
1. I need to know whether I am testing bundle 401 or 402.
2. I need to know whether I am reading the color codes the right way or backwards. I need to know if I am putting them in the chimneys correctly.
3. I need to interpret test results.
4. I need to address the problem with adjusting the pressure in the splicing unit.
2/26: Jim said the test data is being cut off at 675. I should remind Dr. Jones about that before I leave.
The fiber color code is read from the elastic farthest from the code end to the one closest to the code end. By code end I mean the end of the fiber that is closest to the color code.
As I thought, the SiPMs and chimneys closest to the backplane are numbers 1 and 16, and those farthest from the backplane and closest to the door are numbers 15 and 30.
Then bundle I have been testing is number 401, not 402, since the fiber color codes match the ones for bundle 401 given in the [https://docs.google.com/spreadsheets/d/1r0ie8X5TxzoVdzD2mMp-dMf9cRbptE4xoxn2mvrBsro/edit?ts=5a5661a0#gid=1603396283 Summer 2017 Fiber Data Log].
The data log shows yellow as the strap color on the Bundle 401 sheet and pink as the strap color on the Bundle 402 sheet. The Information sheet had the wrong colors for bundles 401 and 402, so I changed them.
I continued polishing the sci-fi bundle. Today I pressed harder and reached my goal with the 400 grit paper, which is to get 0.014" from the final length. I came close to the 0.025" feeler gauge on one end of the bundle and 0.029" with the feeler gauges on the other side.
2/27: I ran four tests on bundle 401. Yesterday Dr. Jones said I should pick the best fibers from this bundle for comparison with future test results. I think I might pick the best three from the fibers set forward and the best three from the ones set back. Since the graphs of the test results give the same mean as the mean in the text logs, I will probably use the mean text log column to pick the best fibers.
However, I would like to know how the standard deviation should affect my choice and what the other columns in the text logs mean.