Choosing the right filament

Filament selection is the single biggest determinant of whether a print succeeds or warps off the bed. Three factors do most of the work:

1. Match the filament to your printer

Most consumer FDM printers ship tuned for PLA. PETG, ABS, ASA, and nylon all need higher nozzle and bed temperatures, and some need an enclosed chamber to print reliably. Before buying anything exotic, check your printer's max nozzle temperature and whether the build plate can hold the bed temp the filament wants.

2. Match the filament to the part

• Display / prototype / low-stress: PLA. Easy to print, cheap, rigid, looks good.
• Outdoors or under load: PETG or ASA. Both tolerate sunlight and modest mechanical stress better than PLA.
• Heat resistance: ABS or PC. PLA softens around 60°C, so a PLA part left in a parked car will sag.
• Flexible: TPU. Slow and fiddly but the only good option for parts that need to bend.

3. Match the filament to your patience

ABS, ASA, and nylon all need an enclosure to avoid warping and delamination. If your printer is open-frame and your room is drafty, PETG is the next step up from PLA in difficulty.

Quick comparison

• PLA: easy, rigid, low heat resistance.
• PETG: tougher, more flexible, prints almost as easily as PLA.
• ABS: heat-resistant, smells, warps without enclosure.
• TPU: flexible, slow to print, finicky on direct-drive only.
• Silk / matte PLA: cosmetic variants of PLA, same printability.

See PLA vs PETG for a deeper dive on the most common toss-up.