Gonna leave it here because someone might find it useful and my googling didn't come up with the answers that I liked.

So. I successfully switched my TerraMaster D2-310 from RAID1 to SINGLE mode, where each physical drive corresponds to a distinct logical one. Despite multiple sources stating that such a switch requires wiping the drives, I found a method that worked for me. Keep in mind that results may vary, and this might not apply to all enclosures.

Here are the steps:

1. Power down the enclosure, disconnect it from your PC, and remove Drive 2 from the enclosure.

2. Connect Drive 2 to your PC motherboard using a SATA cable.

3. Turn on your PC and ensure Drive 2 functions properly, allowing you to read and write data.

4. With the enclosure powered off, switch the MODE setting on the back of the device to SINGLE mode. WARNING: Do not, DO NOT press the Reset button, as it will most likely wipe your drive!

5. Power on the enclosure with Drive 1 inside and connect it to the same PC where Drive 2 is already connected.

6. Windows cannot mount Drive 1 due to its signature matching that of Drive 2, which is desired.

7. Open Disk Management, locate your "Offline Disk," right-click on it, and select "Online." This action changes the signature of Drive 1, effectively removing it from RAID.

8. You can now navigate to the root of each disk and delete any hidden folders containing RAID information. I removed the 2 folders starting with a "." (dot).

That's it. Aside from other obvious benefits of NOT having to tie 2 drives together, I believe I will get better longevity of my second drive now because I will use it to back up only the important stuff once a day.

Ever since getting my benchtop CNC running, I have not been very happy with the lack of manual control over overrides and buttons.

This DIY Engineering video gave me a great idea: build one myself.

I wanted the smooth speed and feed overrides, so I decided to not go with HID device, but instead with a full serial control paired with a custom plugin on the UCCNC side.

Here is the Fusion design of the enclosure:

And here it is 3D-Printed.
Acrylic face engraved from the back side and painted.
And all buttons and controls mounted:

All I have to do now is wire the Arduino board, program the plugin, and test it!

Update:

Here is the video of the pendant in action:

1. PCB Design

Design notes:

• All resistors used were 10K
• Speed and Feed potentiometers are 10K
  Their pinout goes Wiper->ground = 0%, Wiper -> +5V = 200%
• Axis and Handwheel Increment rotary switches are 4-position and their pinout goes like this:
  Axis select 1-X, 2-Y, 3-Z, 4-A, C-Common (+5V)
  Handwheel Increment 1-0.0001, 2-0.0010, 3-0.0100, 4-0.1000, C-Common (+5V)
• All function buttons such as Jog +/-, M1, M2, etc are sending +5V signals to the digital pins D2-D12
• D13 digital pin is connected to a LED indicator and is used to tell the user that the Pendant is allowed to send signals to the plugin.

Design files:

• Electronics Design: https://a360.co/3NGWRTP
• https://a360.co/3NLhfDk
• https://a360.co/3JObaVh 

2. Enclosure Design

https://a360.co/3fG3jgI 

If you don't have a 3D printer and/or a CNC Mill, please contact me and I will send you a 3d-printed enclosure and the 3d-printed or milled acrylic face plate:

• 3D-Printed Black PLA Enclosure (shown in pictures): 30$ + shipping
• 3D-Printed Black PLA Face Plate (optional): 15$ + shipping
• CNC Milled and Engraved unpainted (clear) acrylic Face Plate (shown in pictures): 30$ + shipping

3. Arduino Setup

• Install the Full Firmata library onto your Arduino Nano (Or any other Ardiono that supports USB Serial Communication): StandardFirmata sketch used for Arduino NANO is also added to the release package

• Please note that you might need to install Arduino USB Driver in order for your Arduino to work on the target computer!

4. UCCNC Setup

• Download the latest LEETArduinoPendant from the releases and extract it to your PC.
  https://github.com/swindex/LEETArduinoPendant/releases
• Copy the LEETArduinoPendant.dll plugin file to the C:\UCCNC\Plugins directory!
• Copy the Solid.Arduino.dll file from the Solid.Arduino release folder to the C:\UCCNC directory.
• Please note that you might need to install Arduino USB Driver in order for your Arduino to work on the target computer!
• Launch UCCNC.exe, go to Settings->Configure Plugins, and mark the LEET Arduino Pendant plugin as Enabled and Call startup
• After everything is installed, Arduino is connected and UCCNC is running, press the "Enable" (+5v to D2-B-ENABLE ) button that will tell the plugin that the pendant is ready to send signals! D13 (LED+) will then have a continuous +3.3V signal alerting you of that!

Hardware Acquisition (Amazon)

Fusion F360 desing files Size:2.55 MB

Since my garage/shop has a limited workspace, I have long wanted to upgrade the big and clumsy computer I used to drive my little Prolight desktop CNC to something more elegant and convenient.

TL;DR: You can read about the printing settings and download files on Thingiverse: https://www.thingiverse.com/thing:4754968
Here is the shared Fusion Project: https://a360.co/36UhI15

After quite a bit of googling, and testing the UCCNC control software that i already have I decided to re-use my old Z83 mini-PC with Intel Atom processor.

Then I ordered a SunFounter 10.1" touchscreen monitor with a nice resolution of 1200x800 from amazon.

Since the display does not come with an enclosure I decided to design one myself.
A good opportunity to dust off my 3d modeling skills:

Having done all the motor tuning and testing on the table, it was time to mount everything inside the machine enclosure.

I cut the heatsink to size enough to house four drivers, laid out some mounting holes, and drilled and tapped them M3.
Then drilled clearance holes in both the heatsink and the board and joined them with some 19mm long brass standoffs.

Drilled a hole in the enclosure for the motion controller mounting and LAN cable connection.

Then the main board containing drives and the power board and the breakout board were installed in the machine.
At this point, I realized the drive mounting scheme I chose was a mistake because it was a lot more challenging to connect the wires to the drive terminals so deep and so close to the enclosure. It helped to unscrew the main board, pull it out a little, connect the wires and only then push it back in and screw it to the wall of the enclosure.

Traced all the black cable going to the fuses and found which ones control the spindle and which ones go to the appliance plugs.
By fiddling with the controls on the front of the machine, identified all the wires and their functionality.

The Gecko G320X drives use the same (ERR/RES) pin controlling the drive fault reset and the error status.
When the drive is at fault (every time you startup or when the motor loses too many counts), it has a ground voltage of 0. If you pass +5v, it will reset the fault and enable the drive.

So I had to re-use the red cycle stop button to pul it to +5V when the machine is started. To sense the drive fault and stop the machine I used pin 12 (pull-down) on the C11G BOB. So when any of the drives pull ERR/RES to ground, the C11G board and mach4 react to it like an E-STOP.

The motors mounted back, and the encoder wires soldered directly to the data cable wires of the same colors. For that, I cut off the bulky DB-25 connectors.

Pay attention to the property belt tensioning. According to the manufacturer, the belt should sag a maximum of 1mm under the pressure of about 3 pounds applied at its middle point.

With everything connected, it is time to test the machine. See how it homes and runs!

Laying out holes on the heatsink Everything mounted and connected. What a mess! Wiring Schematics