Printing: from geometry to physical part.
FDM printing starts long before the printer: each part, already designed for the process back in CAD, is oriented on the bed to balance three demands at once — strength (the layers must work in the right direction relative to the loads), the surface finish of the visible faces, and the supports, which drive the look of the part, how easily they come off and the material cost.
Then come the slicing parameters — supports, temperatures, speeds, extrusion width, layer height — tuned part by part according to our priorities, and then the functional clearances, checked iteratively with tolerance tests. Surface finish, strength and material use are optimized together, with the coming small-series production in mind.
Learn more — click a sub-step
01Orienting the parts
A printed part is not isotropic: strong in the plane of its layers, weak in peeling between them. The geometry was already drawn for the process; what is left is choosing, for each part, the pose that makes the layers work in the right direction relative to the loads — the shroud upright so the propeller's load stays in the layer plane, the arm flat to take bending, the base face-down on the plate.
Two further demands play out at the same moment. Surface finish first: visible faces are turned upward or laid against the textured plate, which stamps a regular grain straight onto them — zero post-processing. Supports next: every orientation generates more or fewer of them, and they decide the scars to clean up, the time spent tearing them off and the filament spent for nothing. No pose wins on all three counts: it is a judgment call, part by part.
02The print parameters
Once the part is placed, everything happens in its slicing profile: nozzle and bed temperatures, speeds, cooling, layer height, extrusion width, wall count, infill density and support strategy. Every one of those settings pulls in two opposite directions — a thin layer and a slow speed give a fine surface and crisp details, but multiply machine hours; many walls and dense infill give strength, but weight and filament.
So there is no universal profile: each part gets its own, arbitrated by what is asked of it — looks for the visible surfaces, mechanical strength for the load-bearing ones, economy for everything else. And the layer-by-layer preview acts as a dress rehearsal: walls, infill and scaffolding are all checked before committing hours of printing.
03Materials that fight back
Two of the product's materials sit outside the comfortable range: polycarbonate and TPU. PC shrinks hard as it cools — corners lift, the part peels off the bed, layers split; it calls for high temperatures, cooling turned off and a closed enclosure sheltered from draughts. It is also strongly hygroscopic: poorly dried filament crackles as it extrudes and comes out porous.
TPU has the opposite problem: being soft, it does not push, it compresses. Between the extruder's knurled wheel and the nozzle it buckles and jams the moment speed rises or retraction runs too long — hence low speeds and a touchy setup. It fears moisture too, and its adhesion, to the bed as much as between layers, depends directly on temperature and flow. Each material imposes its own profile, and part of the printing done is only there to find it.
04Tolerances: a loop that never stops
Between the file and the part sits physics: expansion, shrinkage, the real width of the extruded bead. The functional clearances — the hub's fit on the motor shaft, the TPU damper's housing, and above all the blade-shroud clearance the Research step demands between 0.5 and 1% of the diameter — cannot be deduced from a calculation: they are tuned with purpose-printed tests, measured with calipers, fed back into the parametric CAD, printed again.
That loop does not run on its own: it advances alongside the other optimizations, and that is what makes it iterative. Changing a part's orientation, the layer height or the presence of a support moves the real dimensions — a vertical hole and the same hole lying down do not come out the same size. Every gain won elsewhere is paid for with a check here, until the two settle.