The most common 3D printing material is PLA, or Polylactic Acid, a biodegradable thermoplastic derived from corn starch or sugarcane that is prized for being easy to print, typically at temperatures between 190 and 220°C. PETG offers a tougher, slightly flexible alternative with food-safe variants available, printing around 220 to 250°C. ABS, or Acrylonitrile Butadiene Styrene, is durable and heat-resistant but tends to warp during printing and emits fumes, so it generally requires an enclosed printer and good ventilation, with print temperatures of roughly 230 to 260°C. TPU, or Thermoplastic Polyurethane, is a flexible rubber-like filament ideal for gaskets and soft parts, while nylon is strong and durable but notoriously absorbs moisture from the air.
Beyond these common plastics, several engineering and specialty materials expand what is possible. ASA is a UV-resistant alternative to ABS well suited to outdoor parts, and polycarbonate is extremely strong and heat-resistant but harder to print. Composite filaments embed chopped carbon fiber, wood fibers, or metal powder into a plastic base to add strength, stiffness, or special aesthetics, and metal-filled filaments can sometimes be sintered after printing to leave a mostly metallic part. Decorative variants like glow-in-the-dark, silk, and rainbow filaments add visual interest without changing mechanical behavior. Filaments are commonly sold on 1 kg spools, with smaller 250 to 500 gram spools available for experimentation.