8 explainers
Learn
These topics were not guessed at. They come from counting recurring themes across roughly 170,000 archived owner posts — first layers, clogs, stringing, noise, firmware, fumes, resin handling, filament moisture and print times, in that order of frequency. Each answer leads with the short version.
How fast is a 3D printer really?
The number on the box is how fast the toolhead can move, not how fast it can print. Divide the hotend's rated flow in mm³/s by 0.08 and you get the fastest line it can lay at a 0.4 mm nozzle and 0.2 mm layer — usually well under the advertised figure.
Do 3D printers need ventilation?
PLA in a ventilated room is the low-risk case. ABS, ASA and resin are not — those need either an enclosure with real filtration or a window and an extraction fan. Ventilation is a materials decision more than a printer decision.
Why won't my first layer stick?
Most first-layer failures are nozzle height, a dirty plate, or a bed temperature mismatched to the filament. Modern levelling hardware fixes the height part automatically; nothing fixes a plate with fingerprints on it.
Is it safe to leave a 3D printer running unattended?
Modern printers have thermal runaway protection in firmware, which addresses the worst failure mode. The residual risks are mechanical and messy rather than catastrophic — so a camera, a smoke alarm in the room and a printer that is not on a carpet cover most of it.
Does filament really need drying?
PLA mostly tolerates humidity; PETG, nylon and TPU do not, and nylon is the extreme case. Wet filament prints with popping, stringing and weak layers. A few multi-material units dry spools while feeding them, which matters most on long prints.
Do I need a hardened nozzle?
Only if you print filled filament — anything with carbon fibre, glass fibre, glow-in-the-dark or metal in it. Those destroy a brass nozzle quickly. Plain PLA, PETG and ABS do not need one.
Should I buy a resin or a filament printer?
Resin for small detailed things — miniatures, jewellery, dental models. Filament for anything functional, large or that needs to be tough. Resin's detail advantage is real; so is its handling burden.
What does a heated chamber actually do?
It keeps the whole part warm while it prints, so lower layers do not cool and contract while upper ones are still being laid down. That contraction is what makes large ABS parts curl off the plate and split along layer lines.