Test piece with 0.5mm thick circular base and 0.5mm thick 1mm wide circles with 1mm gaps. For testing printer behaviour.

Issues that can be identified by printing this:

• Ability to cleanly print a lot of segments per second. Each ring is made of 240 segments, so the count per second increases from outer to inner circles. – Backlash issues. The rings are normally formatted into two counter-rotating tracks, so that any backlash effect shows up as varying gap between the tracks. – Extruder spillage. The printer should change direction and layer at the same point when printing the circles, and when printing fast with no extruder advance (which is available in at least the Marlin firmware), extra plastic is left at the direction/layer change spot.