I was trying to make a 5 sided knob for my Z-Stop adjuster on my Anet-A8. The M3 bolt used to set the adjustment has 0.5mm pitch, so a 5 sided knob would equate to 0.1mm. However the knob with these numbers on it was far too big. (I will publish the smaller one in another post, but without polymer-clay.)
The question remained though - how to highlight the numbers? I eventually tried Polymer Clay, as advised by my friendly craft supplier in town. I was able to clean up the faces first with wet and dry abrasive paper, and then after it was dry, pressed home the polymer clay into the numerals. To finish I used a sharp blade to simply gut off the excess clay, slicing along the face of the knob. A hair dryer was used to heat the knob up and start the polymerisation. The contrasting purple numbers in the yellow PLA plastic gave the contrast I was seeking.
Depending on the smoothness of the finish there will be some bleeding or irregularities in the characters (see 0&1), however a good finish is possible (see 4).
I am about to transfer my A8 to an AM8, and I have printed the user interface. It has an AM8 banner on it, so I have filled it with Bright Yellow polymer clay. Should look pretty good.
This is not rocket science but others may find the combination of 3-D printing and polymer clay a good trick to keep up a makers sleeve!
NB OpenSCAD previewer here will not render the numbers. I can reassure you, they are in the file.!!!