Sliding Thickness Gauge

This is a thickness gauge that measures up to 10mm with a resolution and accuracy of 0.2mm or better. I realise you can buy a rather more capable digital micrometer cheaply, but I was interested to see how accurate this design would turn out to be. It is a sliding design; to use it you slide the middle part to the left, insert item you want to measure in the gap, slide it back until the item is lightly gripped, and read off the size from the scale. In the photo I'm measuring the thickness of a nut; this device measures it at slightly over 4.2mm, while my micrometer says it is 4.31mm. The model is tuned to come out calibrated on my BambuLabs P1S, but instructions are included below in case that isn't so for you. Printing: The model is printed with outer wall before inner wall, to maximise dimensional accuracy. There are a couple of colour changes such that the inset scale and text is more easily visible, although it would be usable printed in a single colour. There are three par