2025-01-10 | [frame_work]
This is a pretty simple one. I have a security dongle that I use, but I don't want it sticking out from a USB port. On the Framework laptop, removal of one of the expansion modules exposes the underlying USB-C port into which the key can be installed.
A Yubikey 5C NFC has been done before, either in a form that has the end of the key stick out some or one that cuts the rear end off the key to get it to fit. The latter is a better representation of what I want, but I am not so willing to readily modify a security device which is already quite well packaged, even though I am quite good at soldering.
I went with the smaller, non-NFC version of the 5C (but not the extremely tiny nano version). This already fits in an empty expansion slot, and you can still activate the capacitive touch button by reaching a finger beneath the laptop, but for better access and protection I made a 3D printed shell to go around it.
The key simply snaps in place, and is secured by the ENIG plated "wings" which the capacitive touch sensor uses. I could have used the keyring hole also, but putting plastic there in the print orientation I chose would have been difficult to print.
A small piece of shelled wire wrapping wire brings the capacitive sensor connection from the "wings" to an M3 socket head bolt which is accessible from the outside. This is simply wedged in place by the housing, not soldered.
download the .step | download the FreeCad
This model was based off the Framework provided OpenSCAD files, but I redrew them in FreeCAD.
Some use cases will see a security risk in that the key is semi-permanent attached, but this is not part of my model. I use my key mostly as a hedge against SMS / phone-based access, and see a greater risk of the key itself wearing out or becoming damaged if separated repeatedly.