Hole Adheison Test

While printing the first layer, it is sometimes hard to get inner walls that are not connected to anything at the time of printing to stick to a glass bed. Temperature, bed positioning and speed have to be dialed in just right for the first layer to print perfectly every time. This test helps you dial in those settings. Some might even call it... the _hole-y_ grail of first layer adhesion testing.

General advice for better first layers:
* Bed leveling needs to be perfect first, but you might have better results with a bit of z-offset
* Nozzle temp: higher = better
* Bed temp: around glassing point = good
* Extrusion & movement speed: slower = better
* Extrusion & movement speed ramp up (after first layer): slower = better
* Consider compensating for the elephant foot in the slicer after dialing in the settings