How FDM Printing Works: From Spool to Part, One Layer at a Time

Most desktop 3D printers are, at heart, a very precise hot glue gun on a robot arm. In this episode we follow a spool of plastic all the way to a finished part: what fused filament printing actually is, the handful of components that every machine shares, how a 3D model becomes thousands of lines of G-code, and what the nozzle is really doing as it lays down each 0.2 mm layer.

You'll come away understanding why FDM and FFF describe the same process and why only one company can use the first name; what the hotend, extruder, heated bed and gantry each do, and how a bed-slinger differs from a CoreXY machine; the model-to-slicer-to-G-code workflow and the decisions the slicer makes about layers, walls, infill and supports; why a 0.4 mm nozzle, 0.2 mm layers, a roughly 200 °C nozzle and a 60 °C bed are the defaults for PLA; what really drives print time and material cost, with grams, minutes and Australian dollars; and why first prints fail, from poor adhesion to warping and stringing.

For anyone who has never seen a printer run, anyone about to unbox their first one, and anyone who has wondered why their prints come out ribbed. Practical tip from the episode: the strength of a printed part comes mostly from its walls, not its infill, so add a perimeter before you add infill percentage.

Need something printed? Upload your STL, 3MF, OBJ or STEP file at www.3dprinting.zone for an instant price, shipped Australia-wide.

Sources: Prusa Knowledge Base, Bambu Lab Wiki, Prusament and Polymaker technical data sheets, E3D, the RepRap project, Wikipedia (Fused filament fabrication, CoreXY, G-code), Hackaday, 3D Printing Industry, CNC Kitchen.