Compressor wheel extruder indicator

This model is a slightly modified version of [blecheimer's Compressor Wheel](https://www.thingiverse.com/thing:53455). It's been scaled down to about ~34mm OD, and I added a thicker base with a 5mm-ish-deep hole in the center shaped to fit on the end of a NEMA17 output shaft. The fit is pretty tight by design, so you might need to open it up a *tiny* bit with fine-grit sandpaper (a deburring tool works too).

This indicator was designed to fit on a Creality Ender-3 stock extruder without imped