I just printer my first large (for me) print and noticed that the nozzle sounded like it was running into the dry layers below. Eventually the print unstuck and was ruined. When I say large I mean with all dimensions over 100mm. I've calibrated my x,y, and z steps basically to perfection using a 20mm test cube and calipers. I'm currently calibrating my e-steps percisely using a 95% infill test. I am curious why this scraping only presents itself on large prints and usually on the transverses (fast travel movements). Also, there is no visible damage caused by the scraping besides the fact that my prints come unstuck 75% the way through. Have any of you had this issue or an idea as to what may be causing it? Thanks