While plotting the first layer, being around 80% done after plotting for about an hour and a half, my axidraw decided that the y-axis was sitting in the wrong place and jumped down 2 cm.

The lesson here was not to try and plot all the way up to very edge of the plottable A3 area. As you can see on the right, my calibration markers aren't even on the page. Moral of the story: if you tell your robot to go somewhere it can't, it's gonna do its best and try to go there anyway. If it slips a gear or two while trying, that's on you, and that's ok.

As I looked at the boulder rolling back to the bottom of the mountain, I thought "next one will be better, for sure".