@ayrric
We currently use a mix of 4 and 5mm spacers (we have used threaded on older model drones, current ones utilize unthreaded).
4mm are used on certain boards that connect to the underside of the Voxl, such as on the Starling 2 and Starling 2 Max.
5mm are used on most B2B connections on the top side of a Voxl. This has been used on Sentinels and all Starling variants for the Wi-Fi or Modem boards.
I personally am not overly familiar with the components to answer this with certainty, but can say that we do not use any additional heat sinking on Starling model drones. Drones such as a sentinel with an add-on board will have a small fan pre-installed, but that is standard with the base model and on the other side of the board. We do have a small heat sink included with the ToF assembly on Starling 2 and Starling 2 Maxes.
If you are referring to the Starling 2 Image Sensor Adapter, then it can be done in a variety of ways. Our current production process involves connecting the coax to both the image sensors the adapter board before installed to the Voxl 2. In some instances, we do use a bit of foam to secure some of them in place to prevent accidental release. (However, this is primarily a concern with the ToF flex cable, and not the mechanically held in place coax connectors.)
We do also use a little bit of ESD safe tape (Kapton) to hold down some of the thin errant coax wires to prevent them from being pinched in the process of connecting the two boards.
These coax connectors are fairly robust once installed but only rated for (as far as I am aware) roughly 30 connection cycles. So regardless of how or when you choose to install them, take caution in having to do it repeatedly. As long as you provide careful and even pressure when installing them it should be okay.
Hopefully that answered your questions well enough!
