The footprint
It begins as 106 × 96 mm of outline, drawn twice around and filled in. Two blocks, though, not one — the gap between them is the gateway, open from the very first course.
A castle is a stack of terraces, each one carried by the one below it. A printer is a machine that stacks. This one is drawn so the two are the same act: 672 courses of plastic, 12.2 hours, and it lifts off the plate whole — gate, court, round keep, hall and both red roofs, with nothing to assemble and nothing holding it up.
It begins as 106 × 96 mm of outline, drawn twice around and filled in. Two blocks, though, not one — the gap between them is the gateway, open from the very first course.
The passage is 18 mm wide and runs the full 96 mm through the base. Its pointed head steps inward a course at a time until the last open gap, on layer 143, measures 0.24 mm — narrower than the 0.4 mm nozzle that walks across it. Nothing is printed inside the opening to hold it up.
The gate terrace finishes at layer 196, and the court above starts well inside its edge. No sloped face on the model leans further than 39.8° off vertical, and only 11 courses out of 672 have to reach over air at all — window heads, a roof eave — each bridged in a single pass. That is why it slices with supports switched off.
At layer 352 the outline breaks into four: a round keep, a square watchtower, a hall, and the battlemented wall around the yard they share. Three separate buildings from here up, still one object.
The keep's crown leaves the ring wall as 8 separate blocks with gaps between them. Count the battlements on the whole castle and there are 50: 29 around the gate terrace, 13 around the court, 8 up here.
The last course is the point of the watchtower roof, 5.3 in above the plate. 12.2 hours after the first line, and the only thing left to do is lift it off.
Not drawings of the print — the print. Four layers lifted straight out of the sliced file, every stroke one extrusion at its real 0.45 mm width, all four drawn at the same scale. Watch the castle narrow as it climbs: that is the entire reason it needs no supports.
The gateway runs the full 96 mm depth of the base and opens again on the far side: 18 mm across, 28.8 mm to the point of the arch. Until layer 144 the base is printing as two separate blocks, and the two only become one castle when the arch finally meets itself.
The hall, the watchtower and the keep stand on the upper terrace with room to walk between them, inside a wall of 13 merlons.
Stepped where each terrace passes it, and finished with a ring of 8 merlons printed with air between them — the last time on the way up that the outline breaks into separate pieces.
Every number here was measured rather than estimated: the geometry off the mesh that goes to the printer, the weight, the hours and the course count off prusa-slicer over that same file, with supports switched off.
5.3 inches of castle, 6.6 oz in the hand, and not one glued joint.