 Fri Dec 15 14:03:02 2023, Aiden, HowTo, VAC, Vacuum Chamber Opening
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[Aiden]
1. Turn off the RGA filament and disconnect it.
2. Record the pressure and then close the angle valve and gate valve on the RGA line
to isolate it from the system.
3. Turn off the backing and turbo pump and let the turbo pump spin to a stop by slowly leaking the chamber. The slower
the safer.
4.Slowly open the vents on the chamber and the turbo pump. Making sure not to raise the pressure too fast.
5. Once done venting |
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Sun Dec 17 19:43:18 2023, Aiden, Update, VAC, Vac Heating Update
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[Aiden]
I measured the temperature of the flanges where some of the electronics will go and I found that the RGA flange was at 55C and the two full
range gauges were at 65C. I also stopped bake 9 to cool down for measurement. |
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Mon Dec 18 15:51:49 2023, Aiden, Update, VAC, VAC System Heating Update
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After letting the chamber cool down I put the electronics back on and turned the RGA element back on. No data has been taken yet as to let the pressure
continue to fall as the RGA is powered. |
Tue Dec 19 15:45:05 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update 
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| Took RGA data for the macor parts inside of the chamber. With the Ar open the HC levels read 30 torrl/s which is around where it was before the bake. |
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Tue Jan 9 16:35:09 2024, Aiden, Update, VAC, VAC System Leak and Heating
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[Luis, Luke, Aiden]
Leak tested each flange and weld and only found two flanges to have noticeable leaks with the electron multiplier on. These were
the turbo pump flange and the RGA flange that connects to the cross. The RGA one is rather new as it has not had a measurable leak before and it was around
2 e-8. We then applied the new sealant to these two flanges as directed by the instructions on the packaging.
Then after waiting a few minutes for |
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Tue Jan 16 16:11:41 2024, Aiden, Update, VAC,
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[Aiden,Luis]
Below is the data for the most recent bake. I believe the chamber is cleaner than it is actually showing as the RGA data was still getting
lower while the data was being taken. I will take the data again tomorrow just in case. Still, the data shows that the chamber is basically as clean as
it was before bake 10 and this means further power testing can proceed.
Helium leak tested the chamber again today to check if the sealant changed |
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Thu Jan 18 15:13:37 2024, Aiden, Update, VAC, VAC Heating System Update
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[Aiden]
Took more data today and the chamber and elements are showing an even lower HC level than we have gotten before. It is safe to say that the
elements are not contaminated and out gassing HC into the chamber. |
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Fri Feb 2 19:08:20 2024, Aiden, Update, VAC, 1st Hot Element RGA Scan
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| Here are the measurements for the RGA scan of the elements while on at around 160C. The pressure of the chamber during the test was 4.12 e-8 torr. |
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Mon Feb 5 14:17:52 2024, Aiden, Update, VAC, Heater Element RGA Scan
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Here are the new RGA scans for the powered Heater elements. The pressure at the time of taking data was 2.88 e-8 torr. The HC levels are at 40 e-10 torrl/s
which is not bad but still higher than the lowest we have recorded. |
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Thu Feb 8 17:37:48 2024, Aiden, Update, VAC, Heater Element RGA Scan
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Took more RGA data now that the heaters are powered by 18V. The pressure of the system during the data taking was 3.8 e-8 torr. The RGA scans seem to have
gotten worse as well with this power increase. |
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Mon Feb 12 17:35:47 2024, Aiden, Update, VAC, Heater Element RGA Scan
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Took more RGA data before and after increasing the heater elements to 300 degC and before heating them up.
Started Bake 11 as well to hopefully prevent any hydrocarbons from getting captured by the room temperature walls of the chamber. The PID controllers
were set to 100C. |
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Tue Feb 13 12:34:04 2024, Aiden, Update, VAC, VAC Heating System Update
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| Here is an overlay with for all the heating steps done with the heater elements. |
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Fri Feb 16 18:37:28 2024, Jon, Update, VAC, Bake ended 6:23 pm
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I ended the bake of the UHV system (that began on Monday) at 6:23 pm today by switching OFF both PID controllers. The heaters elements were run at max
power (24 V DC / 200 mA per element) during this bake, and I left them powered at the same level.
At the time, the instrument readings were as follows: |
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Mon Feb 19 14:17:50 2024, Aiden, Update, VAC, Heater Element RGA Scan
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Three days after the completion of Bake 11, the Heater elements RGA scan looks much cleaner. The HC level is back down to 33 e-10 torrl/s with the pressure
at 2.13 e-8 torr. I could not take a= scan with the Argon closed as it was left open during the bake and not closed since then. |
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Thu Feb 22 21:48:16 2024, Jon, Update, VAC, Vacuum vent for RGA testing of reflector
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[Jon, Tyler, Luke, Aiden]
Summary
Following Wednesday's cleanroom cleaning [333],
we proceeded to vent the vacuum chamber, remove the heater elements and their mount structure, and install the FROSTI reflectors. The reflectors are the
final components to undergo RGA testing before the FROSTI prototype can be assembled. After installing the reflectors, we pumped the chamber |
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Fri Mar 15 16:58:55 2024, Aiden, Update, VAC, Vacuum Chamber Frosti Testing
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[Luke, Luis, Aiden]
On Thursday, March 14 - Took preliminary RGA scans of the empty chamber to compare later on. Vented the chamber and placed the FROSTI
into the chamber. Plugged in the DB-25 connectors into the feed through port and checked the connection to make sure there were no shorts before closing
the chamber and starting the pumps again.
On Friday, March 15 - The pressure in the chamber has come down to 7 e-6 torr. It seems to be coming down |
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Mon May 13 14:48:27 2024, Aiden, Update, VAC, New Vacuum Chamber Design
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I created a new model for the vacuum chamber based on the ideas from last week's meeting.
It should be noted that we can not have the zero length
reducer and the gate valve on the same arm as they both have blind tapped holes. We need to decide if we want the gate valve or not as if we do, we will
need to use the 3 inch long reducer.
Important Measurements:
From the back of the flange to the back of the RGA: 25.25 in
Height from |
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Mon Jun 3 09:24:48 2024, Aiden, Update, VAC, Vacuum Chamber Rendering
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Here is a new render of the vacuum chamber that includes the 2.75 tee to place the Argon leak right next to the RGA. The conical reducer under the spherical
cube was also replaced with a 4.5 blank. The height from the bottom of the blank to the bottom face of the chamber is 5.45". With the chamber now on 1"
standoffs, we will need a support with a height of 6.45". |
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Tue Jun 25 17:19:42 2024, Luke, Update, VAC, Vacuum chamber leak checking
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Currently our main leak is in the RGA line. We found this by closing the gate valve from the main volume to see if which side was leaking more.
After
identifying this we are pumping down the main volume to see how low it can go the third attachment was taken at 4:16 6/25/24. Pumping started around 3:15.
We have not been able to find exactly which flange is leaking, but our guess is on the small blanks and where the cube attaches to the gate valve |
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Wed Jun 26 16:39:34 2024, Luke, Update, VAC, Vacuum chamber leak checking
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On Tuesday I had isolated the main volume and let it pump down over-night. Today, Wednesday, I checked it and it had only gone down by a small amount compared
to when I left it on Tuesday.
I then proceeded to tighten down the bolts attaching the tubo-pump to the zero-length reducer while it was under vacuum.
This caused the pressure to drop down a few orders of magnitude. |
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Fri Jun 28 18:15:16 2024, Luke, Update, VAC, Vacuum chamber
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We will be configuring the RGA line to remove the spherical cube from the system. Currently our plan for the new design is to connect a 4.5" to 2.75"
Reducing Cross to the gate valve on the vacuum system. It will be orientated vertically with the turbo pump on top coming off the end will be a 90 deg
elbow. On the bottom there will be a 4.5" to 2.75" Zero length reducer attached to that will be a Tee on one side the pressure sensor and the other the |
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Wed Jul 10 17:31:07 2024, Luke, Update, VAC, RGA line disassembly and upgrade
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[ Luke, Cynthia, Michael, Xuesi, Anthony ]
Started work around 12:45
We vented the chamber first and once it reached atmospheric pressure we started taking apart the RGA line. |
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Thu Jul 11 15:53:39 2024, Luke, Update, VAC, RGA line upgrade
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[ Luke, Jon ]
Started work at 11:00
As mentioned in my previous post the RGA was not clearing the table because of a tilt in the cross. So I removed the 90 deg elbow, loosened the |
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Mon Jul 15 13:30:49 2024, Luke , Update, VAC, Problem with 2.75" to 1.33" zero length reducer
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Last Friday while checking the depth of the ZLR I got one of the screws stuck. Today I tried a couple things to get it out. First I tried a few different
pliers to be able to grip lower on the screw this didn't work. So I switched to the other method of drilling a small hole to see if maybe the threads would
pull away from the walls of the hole a bit. This kind of worked as seen in the picture below I was able to remove most of the screw but there is a bit |
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Mon Jul 22 18:19:34 2024, Luke, Update, VAC, Zero length reducer stuck bolts
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Today, I borrowed a bolt extractor drill bit from the machine shop to remove some stuck bolts from the zlr. Before starting, I laid down a sheet of aluminum
foil on the work table and wiped down all the tools I was going to use. I began by drilling a small pilot hole and then enlarged it with a 5/32 drill bit.
However, when I attempted to use the bolt extractor, it didn't grip the bolt effectively. Our bolts were too seized, causing the extractor bit to repeatedly |
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Fri Aug 16 12:51:46 2024, Luis Martin, Update, VAC, Update on vacuum chamber status
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[Luis, Luke, Tyler]
Vacuum chamber parts were finally received and assembled. After whipping down the parts, the blank was removed from the reducing cross. Then,
the zero-length reducer was attached. Lastly, we installed the T that had the argon leak and RGA. The final pump down showed signs of an improved seal |
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Fri Aug 23 16:08:32 2024, Luke, Update, VAC, RGA line leak testing
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[Luke, Luis, Jon, Tyler]
On the 22nd Dr. Richardson showed Luis, Tyler and I how to preform a leak test with the RGA. We did the initiall test and found a few leaks two
were particuarly bad highlighted in orenge below. To try and remidy this we planned on replacing the copper gaskests on the leaking flanges. We then began |
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Tue Aug 27 15:01:26 2024, Luke, Update, VAC, RGA line leak testing
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[Luke, Tyler]
On the 27th Tyler and I ran the RGA leak test again with the electron multiplier on. These were the leaks we measured. The chamber's overall pressure
was at ~6e-8 torr. |
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Thu Aug 29 16:39:34 2024, Luke, Update, VAC, Photos of heater tape 6x
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Sun Sep 1 16:17:40 2024, Luke, Update, VAC, Vacuum chamber leak checking and re-applying heating tape
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[Luke, Luis, Cinthia, Michal, Tyler]
On the 26th Cinthia, Michal, and I took off the insolation on the vacuum chamber and re-routed it to include the new RGA volume.
The next day Luis and I finished up the last of the flanges to be attached. We attached the Pirani gauge with a conical reducing nipple to the |
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Tue Sep 3 15:52:56 2024, Luke, Update, VAC, Heater tape initilization
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[Luke, Tyler, Jon]
On the 3rd we set up the pid controllers for the heater tapes and after putting on the insulation we started heating them up. We first brought
it to ~50C and let it stabilize, there was about a 6-7 degree difference between the RGA and the barrel temperature, with the barrel being higher. We then |
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Fri Sep 6 14:34:52 2024, Luke , Update, VAC, Heating tape work
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On the 5th I had tried to start baking the vacuum chamber however certain parts of the chamber were getting too hot and causing the controllers to shut
off. So I turned them off so that the next day I could rearrange the temperature probes. I then on the 6th set them up so that instead of overshooting
the temperature they would be a little low in places. |
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Mon Sep 9 21:02:37 2024, Luke, Update, VAC, Steadystate temperature of flanges
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I measured the temperature of the flanges and reconnected the RGA turning on its filament. I then turned off the PID controllers.
Here is a table that has the temperature of the different parts of the vacuum chamber.
Electronics
Temperature (C)
Pressure gauge (Main volume)
81
Main |
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Mon Sep 16 13:51:23 2024, Luis Martin, Update, VAC, RGA Scans
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[Luis, Luke}
Three RGA scans were taken. The improvement in the amount of HC in the vacuum is visible across the different measurements.
Images are attached. |
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Wed Sep 25 09:06:09 2024, Luis Martin, Update, VAC, RGA Scans
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RGA
Scan Comparison
The following images compare the RGA scans from 9/23/24, after the first bake with the new vacuum system,
with those from 3/14/24, after bake 12 with the old system. |
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Wed Oct 16 13:58:59 2024, Luis Martin, Update, VAC, RGA Scan
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The following figure displays data acquired on 10/09, and it shows that we are no longer below the cleanliness standard. Also, the system's pressure
went up to 1.9x10-8 Torr (approximately 7x10-9 Torr previously). This might be due to a leak somewhere in the system. More tests
will be performed later. |
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Wed Oct 23 11:48:06 2024, Luis Martin, Update, VAC, Leak Test Results
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[Luke, Luis, Mary, Ma]
On 10/22/24 Luke, Ma, Mary and myself ran a leak test, the results are displayed below. The overall pressure of the vacuum was 2.0e-8 and the
temperature readings were 26C for the RGA and 25C for the main volume. |
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Wed Oct 23 12:08:36 2024, Luis Martin, Update, VAC, RGA Scan
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[Luke, Luis, Mary, Ma]
On 10/22/24 Luke, Ma, Mary and myself ran a RGA scan, the results are displayed below. The overall pressure of the vacuum was 2.0e-8 and the temperature
readings were 26C for the RGA and 25C for the main volume. |
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Tue Nov 5 11:08:40 2024, Luis Martin, Update, VAC, ISO Test
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[Luis, Luke, Ma Michael]
The isolation test was conducted on the vacuum system. Every pump was turned off under vacuum, and pressure measurements were taken
every minute for 15 minutes. The results are displayed in the sheet linked at the end of this report. The pressure of the main volume dropped very slowly.
|
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Tue Nov 19 17:10:34 2024, Luke , Update, VAC, Leak check
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Chamber temperature: 23C
Chamber Initial Pressure: ~1.8e-8 main, ~3.5e-8 rga
Did another leak test after monday's work to check how the seal was holding up initial leak was 5.5e-9. I then tried to tighten the bolts a bit |
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Wed Nov 20 12:31:24 2024, Luis, Update, VAC, Leak test RGA Scan after vacuum repairs
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[Luke, Luis]
After the gasket replacement performed on Monday (11/18/24) we let the vacuum pump down to UHV pressure for a couple days. Today (11/20/24) we
measured the pressure to be 5.30*e^-9 with a temperature of 22C, and we performed a leak test and RGA Scan. |
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Mon Oct 3 17:21:39 2022, Cao, Update, TCS, Inspection of macor parts 7x
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The macor parts arrived and inspected today. These include:
Macor spacer (drawing: LIGO_Redesign_Macor_Spacer_Drawing_v4.pdf
attached below), quantities: 40
No defects, damages observed
Parts are free from grease/ machining fluid
Wall thickness
of 1 mm appear to provide sufficient stiffness to part
Images of parts: Macor_spacer_0.jpg, Macor_spacer_1.jpg
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Thu Jul 27 10:18:43 2023, Celeste, Update, TCS, Graphical Updates to HOM RH Modification
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| Attached are updated graphs of the irradiance distribution from the 1/8th ring heater units (extruded and reduced in length). |
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Fri Jul 28 17:45:45 2023, Celeste, Update, TCS, Graphical Updates to HOM RH Modification, Friday 7/28
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| Updated 1/8th Heater simulation modification graphs. Slides 7, 10, 16-19 are new additions. |
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Tue Aug 1 16:22:35 2023, Celeste, Update, TCS, Graphical Updates to HOM RH Modification, Tuesday 8/1
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| Slides 20-33 are newly added (data/graphs from parameter sweep feature-1/8th heater unit length varied from 10% of original to 100% of original). |
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Thu Aug 10 14:13:38 2023, Celeste, Update, TCS, 8/10/23, Simulation Graphical Progress
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Fri Aug 11 10:57:20 2023, Celeste, Update, TCS, 8/11/23 Simulation Progress
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Tue Aug 15 16:10:06 2023, Celeste, Update, TCS, 8/15/2023 Simulation Progress
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Mon Dec 11 16:20:17 2023, Jon, Summary, TCS, FROSTI Assembly Procedure
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Below is the procedure we will follow to assemble the FROSTI prototype.
Install SS guide rods and bottom Macor spacers in bottom reflector
Install AlN elements on top of bottom Macor spacers
Install
upper Macor spacers on top of AlN elements
Feed unterminated power and RTD leads through slots in upper reflector
Install upper reflector, |
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Mon Feb 26 21:23:27 2024, Jon, Update, TCS, FROSTI Assembly - Day 1 7x
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[Jon, Tyler, Luis, Luke, Mohak, Cynthia, Michael, Aiden]
FROSTI assembly began today. After a final set of RGA scans were taken, the vacuum chamber
was vented and the reflectors were removed. The chamber was then resealed and pumped down again.
Today we completed the installation of the Macor hardware and heater elements between the two reflector halves. Tomorrow we will route, bundle, |