VFA Test for Core XY Printers

IntroductionIf you have not heard of VFAs, it's not too late for you, stop reading this, close this and go live your life!For those who can't unsee it, read on… VFAs are “Vertical Fine Artefacts” and refer to any patterns of vertical or vertical-ish lines that appear on the print surface. They have a variety of causes, and as printing technology develops, some causes are being addressed but new causes are showing up (from faster printing, larger printers and newer motion systems for example). This page attempts to define a comprehensive list of different types of VFAs, how to test for them with new types of tests designed specifically in core XY machines, and potential methods to address them.Types of VFAsI will use the naming convention as started by Taylor from YGK3D in this excellent video about VFAs in modern printers and I've added type 0 and 4 to 7 to the list. Note that I do not agree fully with the video about some points and my description will differ slightly.Type