Nylon 66 (PA 6/6, FDM)

Nylon 66 printed by fused deposition modeling is polyamide 66 supplied as filament and deposited layer by layer through a heated nozzle. The semi-crystalline polymer shrinks considerably on cooling and takes up moisture readily, so parts warp and lift from the bed unless adhesion is good and the chamber is heated, and the filament needs drying before printing. Printed parts are anisotropic, weakest between layers and strongest along the extruded roads, with visible layer lines and small voids between roads. Overhangs usually need supports. It is used for jigs, fixtures, functional prototypes and wear-resistant end-use parts such as brackets, housings and clips.