I got a 3D printer over the break, on the theory that I had wanted one for years and should stop pretending otherwise. The first few days were a steady education in all the ways a first layer can go wrong, which is to say nearly all of them. The machine works fine. The operator needed some calibrating.
The first thing nobody tells you loudly enough: it is almost always the bed. My early prints either refused to stick at all, peeling up into a tangle of spaghetti the moment the nozzle moved on, or fused themselves to the plate so hard I gouged the surface getting them off. Both problems are the same problem, which is the gap between nozzle and bed being wrong by a fraction of a millimetre.
Levelling the bed by paper-drag feel got me most of the way. The thing that actually fixed it was slowing down and watching the first layer go on, every time, with my finger near the stop button. A good first layer looks like slightly squashed lines that have just merged into their neighbours. Too high and you see separate round threads that never bond. Too low and the plastic has nowhere to go and the lines ripple. Once I could read that, the failure rate dropped off a cliff.
The other early lesson was patience with temperature. I had assumed the profile that shipped with the slicer would just work, and mostly it did, but my first roll of filament wanted running a few degrees hotter than the default before layers bonded properly. A small test print, the kind that prints a tower at stepped temperatures, told me more in twenty minutes than an afternoon of guessing. I should have printed it first instead of fourth.
What surprised me was how much of this is about reading the machine rather than configuring it. I came at it expecting a software problem, all profiles and settings, and it turned out to be a craft problem: learning what a good layer looks and sounds like, when to intervene, when to walk away and trust it. There is a real satisfaction in that I had not anticipated.
By the end of the week I had a small box, square corners, clean walls, that looked like I had meant to make it. It is a deeply unimpressive object. I am absurdly pleased with it. The wasted plastic from the first few days is sitting in a sad pile on the bench as a monument to the learning curve, and that feels about right.