Nylon (polyamide) is one of the toughest filaments you can print, but it has a habit that ruins prints before they even start: it drinks moisture out of the air. Damp nylon steams, bubbles and warps, so the first fix is a dryer, not a slicer setting.
Dry it before you print
Polymaker's nylon (PA) printing guide is blunt about this: nylon is hygroscopic and should be preheated at 50–70 °C for 6–8 hours to remove absorbed moisture. It goes further than most materials, recommending that the filament stay in the dryer for the entire time it is being printed, and that it be stored in airtight containers with desiccant to prevent rehydration between jobs.
Bed temperature and the build surface
Once the filament is dry, give it something to stick to. Polymaker lists a 70–100 °C heated bed as critical for nylon adhesion, and recommends a build surface of PEI sheets, Magigoo, or a glue stick (PA guide). This lines up with Simplify3D's bed-adhesion guide, which explains that a heated bed keeps the first layer from shrinking and peeling as it cools.
Enclosure, drafts, and speed
Nylon shrinks as it cools, and drafts make it curl. Polymaker says an enclosure is required for open-frame printers to minimize warping and drafts, and recommends printing at 30–60 mm/s because slower speeds enhance layer bonding (PA guide). Simplify3D's warping guide describes the same mechanism — plastic shrinking as it cools pulls corners up — and recommends an enclosure plus reduced cooling to keep every layer warm.
Nozzle temperature by grade
Set the nozzle to 220–260 °C, with Polymaker noting that PA12 typically prints at 230–250 °C and that other grades vary (PA guide). Polymaker also flags a hardware note worth heeding: use an all-metal hotend for any nylon that needs more than 240 °C. For stringing, Simplify3D's stringing guide recommends retraction of roughly 0.5–2.0 mm on a direct-drive extruder and lowering the nozzle 5–10 °C if the hairs persist.
FAQ
Why does wet nylon ruin prints?
Because the moisture turns to steam in the hot end, leaving bubbles, weak layers and stringing. Polymaker points out that nylon can even absorb moisture after printing, which may slightly change part dimensions.
Can I skip the enclosure with nylon?
Only with a filament made for it. Polymaker notes that its Warp Free nylons do not need an enclosure or a heated bed, while standard nylon on an open-frame printer does.
How strong is nylon compared to other filaments?
Polymaker lists tensile strength up to 80 MPa with 15–30 % elongation at break, and thermal stability up to 120 °C — which is why it is used for gears, brackets and snap-fit parts (PA guide).