Make the body, and make it survive.
A robot's body takes loads a display model never does: torque at the joints, vibration in flight, impact on landing. Printing for Physical AI is its own craft. This is the practical guide (materials, tolerances, joints, and strength) anchored to the Bambu Lab workflow so you go from plate to bench with parts that hold.
What we build on: Bambu first, Prusa CORE One next.
We start with the Bambu Lab ecosystem for the community and the tested profiles, and add the Prusa CORE One as the open, no-lock-in machine. The craft on this page carries to any FDM printer, we're printer-agnostic.
Bambu Lab A1
$399 · bedslinger · AMS LiteThe accessible on-ramp: PLA, PETG, and TPU on an open frame. Where most maker builds begin.
Bambu Lab P1S
~$699 · enclosed CoreXY · AMSThe value enclosed workhorse: handles ABS and ASA for parts that take heat and load.
Bambu Lab H2D
~$1,899 · 65 °C active chamber · dual-nozzleBambu's machine for the hard plastics: CF-nylon and PA at 350 °C.
Prusa CORE One
$1,199 / $949 kit · enclosed + active chamberOur next printer: an open, repairable, no-DRM CoreXY with an active chamber. The trustworthy counterweight to a locked ecosystem.
QIDI Plus4
~$700 · 370 °C · active chamberThe engineering-plastics value pick: reliable PPS-CF and PA-CF well under $1k.
Elegoo Centauri Carbon
~$300 · enclosed CoreXYThe cheapest enclosed machine: CF-PETG and ABS brackets at an impulse price. One per bench.
Sovol SV08
$599 · open Voron · 350 mmThe open big-format play: a real Klipper Voron; add an enclosure for ABS and ASA.
The full landscape: printers, boards, sensors, and open robots in the wild: the Maker Atlas →
What to print robots in.
Start at PLA for shape, move up only as the part demands. Most of a robot is PETG; the flexing bits are TPU; the parts that decide the build are nylon or carbon-filled.
Prototypes & jigs
Stiff, dimensionally accurate, and the easiest to print, but it softens around 60 °C and creeps under sustained load. Great for mock-ups and fit checks; not for a motor mount that gets warm or a part under constant stress.
The robot default
Tougher, more impact-resistant, and more heat-tolerant than PLA, and still easy to print. Most structural parts (chassis, brackets, arms) start here and only move up if they have to.
Heat & the outdoors
Handles a hot electronics bay or direct sun (ASA is UV-stable) and takes vapor-smoothing. Wants an enclosure to print without warping, the trade for its durability.
Anything that flexes
Feet, bumpers, compliant grippers, tires, and cable strain reliefs. Print it slow; 95A shore is a forgiving all-rounder, softer shores for more give.
Load-bearing & gears
Stiff, strong, and abrasion-resistant: the endgame for structural arms, gears, and drive parts. Needs a hardened nozzle and dry filament; worth the fuss where strength decides the build.
The numbers that separate a demo from a robot.
FDM parts aren't dimensionally exact, so you design the gap. These are solid starting points, dial them to your own printer in small steps.
Clearance / moving fit
Print-in-place hinges and anything that must rotate or slide freely off the plate. The workhorse gap for robot joints.
Location / snug fit
Parts that locate precisely but still come apart by hand, alignment pins, stacked plates, lids.
Press / interference fit
Bearings, dowels, and pins pushed home and staying put. Tune in 0.05 mm steps; your printer's real tolerance decides the number.
Holes for shafts
FDM holes shrink and go slightly oval. Model a touch small and drill/ream to size, or a shaft rarely fits its nominal diameter.
Screw threads
Printed fine threads strip fast. Design bosses for heat-set inserts or captive nuts anywhere a screw goes in and out repeatedly.
Motion built into the print.
The trick that makes printed robots cheap: geometry that already moves, or that captures the one metal part that has to.
Motion off the plate
Design the moving pair with a ~0.2 mm gap and it comes out already articulating, no pins, no assembly. The basis of most printed grippers and hinges.
Flex where you want it
A thin flexure (PETG or PP) bends thousands of times where a rigid part would need a pin. Keep the hinge thin and short, the panels stiff.
Metal where it counts
Trap a nut, bearing, or magnet mid-print by pausing, or design a slot it drops into. Metal takes the load a plastic thread can't.
Bigger than the plate
Break a large body into printable sections with dovetails or bolt flanges and alignment pins. Design the seam where the load is lowest.
Print it so it holds.
A moving machine loads its body in ways a display print never sees. Four choices decide whether a part survives the first hard landing.
Layer lines are the weak axis
A part peels apart between layers far easier than it breaks across them. Orient so the load pulls in-plane, not perpendicular to the layers, this one choice often doubles a bracket's strength.
Perimeters carry the load
For stiffness, three or four perimeters beat cranking infill. Infill supports the walls and top layers; it isn't where a loaded part's strength lives.
Capture the body
Cradle the servo or motor body and bolt through its own mounting holes. Don't hang a moving actuator off print-in screw threads, vibration finds them.
Damp the buzz
A flying or walking robot shakes its own screws loose. Thread-locker, nyloc or captive nuts, and TPU washers keep a build together past the first minute.
Plate to bench.
We anchor to Bambu because the community and the parts are already there, but the craft carries to any FDM printer.
Start from MakerWorld
Remix an existing body or start clean. The printed parts for maker builds live here, free to fork.
Slice with intent
Set the material, walls, and orientation from the sections above, the profile is part of the design, not an afterthought.
AMS for multi-material
Print rigid frame and TPU feet in one job; use color to mark orientation or moving parts. One plate, one assembly.
Organize the build
Split a robot across labelled plates, print the load-bearing parts in the strong orientation, and keep the settings that worked with the files.
Printable bodies, growing.
Bodies for the builds on this site (brain-agnostic, printer-agnostic, Bambu-anchored) each with the material, orientation, and print settings that were actually run.
◱ Modeling Files land here as each build is verified on a real printer. Kits follow once the library is rich enough to box.
See the builds →Design a part in the Studio →The design method →