Spent a little time creating some STEP files in ALibre Atom and printing them out in ABS-GF filament.

Not a very clear photo due to lack of illumination, but from top left clockwise, they are: vice jaw protectors, both grooved and plain, “parallels” and assorted angle plates. The one with a flange is for a specific job to set a workpiece at 12.5° in the mill vice. The parallels are surprisingly parallel, to within 0.5 to 1 thousandth of an inch, measured with a digital caliper. That’s good enough for me. How well they all stand up to workshop (ab)use remains to be seen. Easy enough to print off some more if necessary.
John