Here is the SInclair QL Microdrive that was never released to the market.
There is only an AD that picture it, it seems that the original prototype got lost. And Rick was fine on this design (for who know who he was ;-) )
This version is designed to host the vDrive accessory as the Sinclair Microdrive hardware never get to the market either.
There are three files, the bottom one, the original top and the modified top one for the users that want to highlight they are using the vDrive.
The vDrive need to be adapted in high as it was designed for the standard Sinclair ZX Spectrum Microdrive.
Oher Sinclair parts: https://www.thingiverse.com/Matto68/collections/sinclair-ql