 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 |
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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Sat Jul 13 15:09:04 2024, Luke, Update, General, Ring heater COMSL model update
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After the feedback from last meeting and Liu's help narrowing down what I should do to improve the model. I made some changes: First with Liu's help
I made the proportions of the test mass and ring heater much more reasonable and parametrized by constants. Second from Cao's paper "FROSTI Nonimaging
Reflector Design" Liu showed me what I should do to define the elliptical mirrors. Third during Friday's modeling/programming meeting walked me through |
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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 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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Tue Aug 27 18:37:40 2024, Luke, Update, Interferometer Simulations, Ringheater model update
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Updated the model to produce a more circular deformation in the HR surface. The first three attachments are from irradiance patterns gotten from ray tracing.
The last is from a pre-defined irradiance pattern. |
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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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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 07:28:16 2024, Luke, Update, Interferometer Simulations, Ring heater update
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| |
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Mon Sep 23 08:29:49 2024, Luke, Update, Interferometer Simulations, Ringheater update
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Ringheater Update
If the link does not work here is the file. |
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Sat Nov 30 12:41:42 2024, Luke, Update, VAC, Vacuum bake end
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The vacuum chamber has stopped bakeing.
Current state as of 12:10, 11/30/2024:
The gate valve is open, and the filament of the RGA is on. |
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Thu Dec 19 12:00:44 2024, Luke, Update, VAC, End of bake
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The vacuum chamber has stopped baking.
Current state as of 11:40, 12/19/2024:
The gate valve is open, and the filament of the RGA is on. |
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Mon May 26 11:15:28 2025, Luke, Update, Scripts/Programs, Update to optimization plots
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I have created some new optimization plots. I have also started on a model like the previous Desmos model, but in python.
Slides |
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Thu Nov 16 17:12:42 2023, Luis, Shane, Mohak, Update, Cleanroom, Cleanroom cleaning and particle count
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[Shane, Luis, Mohak]
cleaning cleanroom and particle count
3:37 pm: started particle count
zone 3: 0.3 u: 12050.5 u: 7481.0 u: 249
zone
4: 0.3 u: 14960.5 u: 7481.0 u: 290
3:57 pm: began surface check and wipedown, including |
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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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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 09:56:04 2024, Luis Martin, Update, Clean & Bake, MR Bake
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[Luke, Luis]
On Friday, 11/1/24, the MR was unpackaged and cleaned under the flow bench. We noticed an ink stain on one of the corners of the
material. After wiping it down with IPA and Vector Alpha wipes, the stain was removed. However, the material showed some wear.
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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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Thu Dec 5 10:31:13 2024, Luis , Update, VAC, RGA Scan and RGA updates
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[Luis,Shane]
An RGA scan was taken on Dec 4th. The results are attached at the end of the e-log. As we can see, the scan results are under
the allowed limits. After the scan, Shane and I worked on the vacuum connections. The filament was turned off, and the RGA was disconnected from Spica. |
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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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Wed Dec 11 16:06:05 2024, Luis, Update, VAC, RGA Status
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[Luis]
I rebooted Spica and I was able to connect the RGA again. After Connecting the RGA, I left the filament on. |
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Thu Dec 12 13:06:39 2024, Luis, Update, VAC, RGA Scan and vacuum system updates
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[Luis, Luke]
RGA Volume: T = 21°C, P = 1.74e-9 Torr
Main Volume: T = 22°C, P = 5.60e-9 Torr
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Sat Dec 14 07:58:25 2024, Luis, Update, VAC, Vacuum sytem staus and Viton O-rings
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[Luis]
RGA Volume: T = 23°C, P = 1.71e-9 Torr
Main Volume: T = 22°C, P = 5.71e-9 Torr
On 12/13 I took another RGA scan to verify the state of the vacuum system and to see whether the degassing of the filament had worked. The |
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Mon Dec 16 21:32:21 2024, Luis, Update, VAC, MR Testing
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[Luis, Luke]
The MR material was placed in the vacuum chamber following standard procedures to ensure the vacuum remained as clean as possible.
During this process, we only opened the main
volume while keeping the gate valve between the two volumes closed to maintain the UHV in the RGA section.
An
RGA scan was taken before this process, this will be used to compare the state of the vacuum with the sample inside to determine whether the MR material |
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Tue Dec 17 13:53:53 2024, Luis, Update, VAC, Vacuum system status
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[Luis]
The vacuum system is being baked. I disconnected the digital gages and the magnets, opened the Ar leak and started the bake by taking
the temperature from 60C-90C-125C waiting about 15-20 minutes between each interval. The RGA electronics were left on since the temperature of the flange
was 36.6C (bellow the 60C threshold) |
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Sun Dec 22 20:43:35 2024, Luis, Update, VAC, MR Testing
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[Luis, Luke]
RGA Volume: T = 23°C, P = 3.0e-9 Torr
Main Volume: T = 22°C, P = 9.90e-9 Torr
After letting the vacuum cool down for a couple days, we reattached the magnets and sensors, then we performed a RGA scan of the vacuum system, |
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Thu Jan 2 17:52:58 2025, Luis, Update, VAC, MR Testing Continuation
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[Luis, Luke]
RGA Volume: T = 22°C, P = 2.10e-9 Torr
Main Volume: T = 21°C, P = 5.71e-9 Torr
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Tue Feb 11 08:07:02 2025, Luis, Update, VAC, Bake stopped
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[Luis, Ma]
Feb/10/25 4:00pm
Bake was stopped. |
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Fri Feb 14 11:57:50 2025, Luis, Update, VAC, Vacuum Update
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[Luis]
Feb/11/25 9:30am
Pressure gages were connected. |
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Fri Feb 14 12:15:23 2025, Luis, Update, VAC, Vacuum sytem staus
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[Luis, Luke, Ma]
February 12, 2025 - 4:00 PM
We performed an RGA scan with the vacuum system containing the heater elements. The results are attached below. |
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Thu Feb 20 17:07:36 2025, Luis, Update, VAC, RGA Scan
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[Ma, Luis]
February 20, 2025 - 3:30 PM
Ma performed an RGA scan with the vacuum system containing the heater elements. The results are attached below. |
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Mon Feb 24 17:50:13 2025, Luis, Update, VAC, RGA Scan
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[Ma, Luis]
February 24, 2025 - 1:00PM
Ma performed an RGA scan with the vacuum system containing the heater elements. The results are attached below. |
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Mon Apr 28 22:08:28 2025, Luis, Update, VAC, Vacuum Leak Test result
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[Ma, Luke, Luis]
April 24, 2025
3:00 PM |
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Wed Apr 30 15:43:56 2025, Luis, Update, VAC, Vacuum Update
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[Ma, Luke, Luis]
April 29, 2025
3:30 PM |
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Thu May 8 17:41:56 2025, Luis, Update, VAC, RGA Scan Post Bake
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[Ma, Luis]
After taking the RGA scans of the new system, here are the results of the raw and normalized data.We can see that in the post baked system
the He peak is way lower, and the peaks around 20AMU are also significantly lower. |
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Fri Jun 14 13:32:13 2024, Liu, Update, Scripts/Programs, COMSOL simulation on rectangular heater elements design 6x
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I have been looking at the feasibility of an alternative heater element design for FROSTI that replaces the original ring-like heater elements with n
rectangular elements with straight edges. They form an n-sided regular polygon that could well approximate the original annular ring if n is large enough.
This eliminates curved surfaces requirement for the heater elements, which was the source of the many month production delay for the prototype parts. |
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Mon Jun 17 11:47:46 2024, Liu, Infrastructure, General, Temporary cooling units for the labs
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Below are the temporary cooling units installed last week in labs 1119 and 1129. They are the temp. replacement for the building AC system, which will be
shut down during the Physics roof replacement. |
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Fri Jun 21 11:47:30 2024, Liu, Update, Scripts/Programs, COMSOL simulation on alternative straightened heater elements design 6x
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In the previous post, we saw that for the heater element design with straight
edges in replacement of the current eight-element ring-like design, it provides the similar Gaussian-like irradiance profiles, but with smaller power delivery
efficiencies, as shown in the plot. This turned |
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Thu Jun 27 11:09:14 2024, Liu, Update, Scripts/Programs, Straight edge STEP files and ray loss analysis
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Drawings and CAD models of the straight-edge designs are exported, and are visualized in SOLIDWORKS. Two are attached. One is a single edge of the evenly
spaced polygon design with 16 edges, and the other is the 8x2 design, with two neighboring edges grouped together to replace the original single curved
heater.
For the straight edge design in COMSOL, ray power detectors were placed at the heater's front surface. The irradiance is shown in |
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Fri Jul 5 13:17:44 2024, Liu, Update, Interferometer Simulations, Four-quadrant FROSTI-like RH for astigmatic thermal actuation for CE optics 7x
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In the CE corner layout design and down selection study, interferometer layouts with large incidence angles on some of the curved optics are being considered,
such as the folding mirrors in the "long crab". This however generates astigmatic beams upon reflection and results in mode mismatches in coupled cavities
that need to be mitigated. Astigmatic thermal actuation for the optics involved is thus essential. One way we are considering is to implement a FROSTI-like |
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Fri Jul 5 14:12:32 2024, Liu, Update, Interferometer Simulations, CE BS Mechanical Resonances
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The butterfly and drumhead mechanical modes for the aLIGO BS were calculated in COMSOL. The resonant frequencies for the two acoustic modes are 2.45
kHz and 3.61 kHz, matching the results in reference
for instance.
For a quick projection for the resonant frequencies going from aLIGO to CE, the height and width of the BS are increased assuming |
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Fri Jul 5 14:23:13 2024, Liu, Update, Interferometer Simulations, Engineering drawings for straight edge heater element designs for FROSTI
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Step files and engineering drawings for the straight edge heater element designs have been created in COMSOL and SolidWorks. They are available in the group
Git
Repo. With those, we will initiate a discussion with the ceramics supplier for an estimate of the feasibility and benefits of the straight edge element |