The details of the handles and hinges are great, would you please explain how you accomplished it.
The models are, of course, created in TurboCAD in the usual way - modeling, materials, lighting, RSE & RSL. I then create viewports and print one quality render and one hidden line render (.012" Line Weight) to PDF. I then open both PDFs in Photoshop and remove the background from the rendered image. The hidden line opens up with just lines so it really doesn't require much additional work. In Photoshop I place the HL image on a layer above the QR and line them up. Photoshop, like TurboCAD, uses snaps so getting them lined up is a breeze. I occasionally will erase some extraneous lines from the HL layer, like I did with the hardware in this project. TurboCAD does have the capability of either layering viewports as can be done in Photoshop or one can even use the camera properties to show rendered objects with suppress Hidden Line engaged. I prefer to use Photoshop for this final output since one is more able to edit the individual layers. If you just output from TurboCAD with the single render it is much more difficult to remove unwanted hidden line pieces. Another nice thing about creating the final output from Photoshop is one can tweak the rendered images if one finds the output from TurboCAD is not quite what was hoped for, or a client wants a color change, or some part darker. This is fairly easy in Photoshop and saves having to experiment further in TurboCAD to get a better render. This is a pretty general overview - hopefully it helps.