Trouble with Adjust Z  

Trouble with Adjust Z

I have got my i3 MK3S+ (kit) up and running and it has passed all of the self tests, except I am having some difficulty with the "Adjust Z" procedure. I have adjusted the nozzle down, all the way to -2.000mm, and I am still not getting the results shown in the 3D Printing Handbook, pp. 26–27.

The pattern of lines on the steel plate does not have the sharp corners illustrated in pict. 10. When the line makes a sharp turn, the print head pulls a bit of the filament off the plate, making a diagonal, rather than a square corner. I assume this is not what's supposed to happen. Pict. 11 is not easy to interpret—a good high res photo would be more helpful. Is the filament in the "Perfect" section supposed to be fused together like the first layer of a printed object? That's not what I'm getting, it's more like the fibers in a shredded wheat biscuit, and it comes apart when I pull it off the plate.

p. 26 says if you have to adjust the nozzle lower than -2.000, move the SuperPINDA probe "slightly higher." "Slightly higher" is a rather vague instruction. I find it difficult to move the probe accurately by small increments. The corrugations on the surface of the probe are responsible, I think (a different surface would make to process easier). Using a zip tie to calculate the height of the probe above the bed seems like a rather crude way to do things.