3D printing produces rigid plastic parts from a digital model, and in puppet building its value is in the pieces that need to be precise, repeatable or identical.
What it is genuinely good for
Eye mechanisms and sockets. Mouth plate formers. Servo mounts and brackets for animatronicsAnimatronics is the use of motors, servos, cables and electr... More. Arm rod grips and pivots. Jaw hinges. Anything mechanical, anything that must be dimensionally exact, and above all anything you need more than one of.
What it is bad for
The puppet itself. Printed plastic is rigid, heavy for its volume, and completely wrong as a skull that a hand lives inside for hours. A printed head does not breathe, does not compress and does not forgive. Foam earned its place for reasons a printer does not change.
Where it quietly wins: repeatability
A troupe needing four matching puppets can print four identical eye assemblies and four identical mouth formers, then build the soft parts by hand around them. That combination — printed skeleton, hand-built body — is far more practical than trying to print a character.
Materials
PLA is cheap and easy and fine for parts under no real stress. PETG is tougher and handles flex better, which suits hinges and anything performed with. Flexible filament exists and is genuinely useful for small squashable features.
Print in orientation
Printed parts split along their layer lines. Orient any part that takes load so the force runs across the layers rather than trying to peel them apart, or a hinge will snap on its first hard open.
The hack: print the part, then test it in the mechanism before you model version two. Tolerances that look correct on screen are frequently wrong by half a millimetre in the hand.