Heads up: many models on this page are AI-generated or uploaded untested. They may be misconfigured for the intended application — check the dimensions and tolerances, and verify or edit the model before printing or relying on it.*
Forearm Wrist Link
This is the elbow-to-wrist link of the 'SG90 Four-Axis Desktop Robot Arm' kit. It is a flat bar 5 mm thick and 18 mm wide, 83 mm long from the elbow axis to its rounded tip. The Ø26 × 6 mm elbow hub screws to an SG90 double-arm horn. The horn sits in a 7.5 × 36 × 1.8 mm pocket that has a short rear lobe so the slot is fully walled, with a Ø5.3 hole for the horn screw. The flat wrist end carries the gripper palm on two M3 bolts through Ø3.4 holes 15 mm apart, at 60 and 75 mm from the elbow axis. Their M3 nuts sit in 5.7 mm captured hex pockets on the underside.
Upper Arm Elbow Link
This is the shoulder-to-elbow link of the 'SG90 Four-Axis Desktop Robot Arm' kit. It is a 5 mm flat bar, 22 mm wide, 80 mm between axes and 119 mm long overall. The Ø24 × 9 mm shoulder hub has a double-arm SG90 horn pocket on the bottom face (7.5 × 36 × 1.8 mm, Ø5.3 screw hole) and a Ø16.05 × 5 mm press-fit pocket on top for a 625 bearing (5 × 16 × 5), with a 2.2 mm web between them. The elbow end has a 28 × 12.6 mm SG90 window with M2 ear slots, which puts the elbow servo shaft at 80 mm.
Yaw Turntable Shoulder Yoke
This is the Ø84 x 5 mm yaw turntable for the 'SG90 Four-Axis Desktop Robot Arm' kit. It screws to the yaw servo's double-arm SG90 horn through a 1.8 mm underside pocket with a Ø5.3 centre hole. It also has an upright 5 mm wall with a 28 x 12.6 mm SG90 window and M2 ear slots, which puts the shoulder axis 38 mm above the underside. Two gussets brace the wall, and two Ø9 bosses carry Ø4.0 x 6 mm M3 heat-set bores at (22, ±14) for the 625-bearing idler cheek.
SG90 Arm Base Pedestal
The base and yaw-servo housing of the 'SG90 Four-Axis Desktop Robot Arm' kit. It is a hollow 100 x 100 x 40 mm pedestal with a 5 mm top deck. The deck has a 28 x 12.6 mm SG90 window with 2.4 mm M2 ear slots, which puts the yaw shaft at the deck centre. It screws down with four #8 wood screws through Ø4.8 holes in corner columns on an 84 mm square, and a 14 x 8 mm notch lets the servo cable out.
Rover Sensor Bumper Plate
An L-bracket front bumper for the 'N20 4WD Skid-Steer Rover Base' kit. Its 16 x 60 x 4 mm base bolts to the chassis plate at (68, ±15) with M3x12 screws and nuts, sitting in 6 mm counterbores. The 60 x 40 x 4 mm face wall has a 5 x 3 grid of 3.4 mm M3 holes on a 10 mm pitch for mounting sensors, and two 3 x 8 mm zip-tie slots. It prints on its side so bumper impacts load along the layers, not across them.
Pi 4 Rover Deck With Legs
A 120 x 90 x 3 mm raised electronics deck with four integral 10 mm legs, part of the 'N20 4WD Skid-Steer Rover Base' kit. The legs stand it 40 mm above the chassis plate, and each foot takes an M3 heat-set insert (4.0 x 6 mm bore) for M3x8 screws from under the chassis. The deck has 2.9 mm M2.5 holes on the Raspberry Pi 4 58 x 49 mm pattern with 6 mm x 3 mm spacer bosses, a 4 x 7 grid of 3.4 mm M3 holes on a 10 mm pitch for a motor driver or ESP32, and two 30 x 10 mm cable windows.
56 mm Set-Screw N20 Wheel
A 56 mm OD x 13 mm wide drive wheel for the 3 mm D-shaft of an N20 gearmotor, part of the 'N20 4WD Skid-Steer Rover Base' kit (print 4). It has a 3.3 mm bore, an M3 set screw with a captured M3 nut in a drop-in slot, a 4 mm access hole in the rim for the hex key, and two 3 x 1.5 mm tread grooves for rubber bands or O-rings. You can take the wheel off and put it back on as often as you like without the bore wearing loose, which is how press-fit hubs fail.
N20 Gearmotor Tunnel Clamp
A 24 x 26 x 22 mm block that holds one N20 micro gearmotor under the chassis, for the 'N20 4WD Skid-Steer Rover Base' kit (print 4). The gearbox slides into a 12.4 x 10.4 mm open-ended tunnel with 1 mm lead-in chamfers, and an M3x6 pusher screw in a 4.0 mm heat-set insert clamps it in place. Two M3 heat-set bores (4.0 x 6 mm, 16 mm apart) take M3x8 screws from the plate top.
N20 Rover Chassis Plate
A 150 x 96 x 4 mm chassis plate that sets the layout for every other part in the 'N20 4WD Skid-Steer Rover Base' kit. It has 3.4 mm M3 through-holes for four N20 gearmotor clamps, the Raspberry Pi 4 deck legs, a 2S 18650 battery cradle and the front sensor bumper, plus motor wire slots, two 30 x 8 mm wire pass-throughs and a 2 mm stiffening rim on the sides and rear.
Tilt Axis Idler Pivot Post
This is the idler pivot post for the 'SG90 Animatronic Eye Mechanism' kit. The tilt paddle's left arm turns on an M3x16 SHCS, M3 washer and M3 nylock through the post's Ø3.4 hole at y -45, z 30, directly across from the SG90 tilt servo. The wall is 6 mm thick with a flat inner face and a rounded top, and two gussets brace it. The 4 mm foot (about 20 × 34 × 40 mm overall) has a 3.4 mm slot with end centres 20 mm apart. Two M3x10 SHCS and nuts go through deck holes (-60, -40) and (-60, -50), and the slot lets you slide the post ±5 mm to line it up with the servo shaft. Fit the foot screws without washers so the heads clear the gussets.
Twin-Slot Eye Tilt Paddle
The U-shaped tilt rocker (96 × 37 × 18 mm, black) for the 'SG90 Animatronic Eye Mechanism' kit. It pivots on the y -45 / z 30 axis between an SG90 horn and an M3x16 idler pivot. Its 3 mm crossbar has two 22 × 4.2 mm rounded slots on a 60 mm pitch that steer the M3x35 eye-stalk screws. The right arm has a flat outer face for the stock SG90 horn (2 servo self-tappers) and a Ø7 hole for screwdriver access. The left arm has a Ø3.4 hole for an M3x16 SHCS, washer and nylock.
Pan Scotch-Yoke Tie Bar
This is the red tie bar for the 'SG90 Animatronic Eye Mechanism' kit. It is 74 × 30 × 5 mm and connects both eye-yoke pan levers through Ø3.4 holes on a 60 mm pitch, using M3x8 SHCS and M3 washers. Its centre tongue has a 2.6 mm slot (end centres 14 mm apart) with 0.4 mm chamfers on both faces. The M2x16 pin on the SG90 pan horn runs in this slot, forming a scotch yoke that pans both eyes together.
Animatronic Eyeball
A Ø30 mm eyeball for the 'SG90 Animatronic Eye Mechanism' kit (print ×2). It prints standing on its flat Ø25.4 mm rear face. The side flats sit 29 mm apart and each has a Ø2.6 × 8 mm self-tap bore for the M3x12 SHCS tilt pins through the gimbal yoke. A Ø2.6 × 12 mm rear bore takes the M3x35 stalk screw that the tilt paddle steers. On the front is a dished Ø12 mm iris and a Ø5 mm pupil recess, ready for paint or a sticker.
Eye Gimbal Pan Yoke
A U-shaped gimbal yoke for the 'SG90 Animatronic Eye Mechanism' kit (print ×2). Each yoke holds one 30 mm eyeball so its pan and tilt axes cross at the centre of the eye. The 41 × 10 × 5 mm bottom bar pivots on the deck using an M3x16 SHCS, a washer and an M3 nylock through a Ø3.4 bore. The two 5 mm uprights have Ø3.4 tilt holes at z 29.5, 31 mm apart on their inner faces, and take M3x12 SHCS that screw into the eyeball. A +Y lever with an R7 pad has a Ø2.6 self-tap hole 20 mm from the pivot for the M3x8 tie-bar screw.
Animatronic Eye Deck Plate
This is the 140 x 150 x 3 mm base deck for the 'SG90 Animatronic Eye Mechanism' kit. It has a 10 mm grid of Ø3.4 M3 clearance holes, with the eye-yoke pan pivots at (±30, 0). There is a 12.6 x 23.0 mm through-pocket for the SG90 pan servo, plus slotted tab holes for its M2x8 screws and nuts. Underneath, 25 mm corner legs and 3 x 6 mm ribs keep the servo body and the M3 screw heads and nuts off the table. The part prints top-face-down with no supports.
Tilt Sensor Cradle Face
This is the lockable tilt head for the 'NEMA17 Geared Radar Scan Turret' kit. It is a 55 x 40 x 4 mm face plate with a 5 x 3 grid of 3.4 mm M3 holes at 10 mm pitch and two zip-tie slots at X ±24. The plate sits on two 34 mm deep side flanges that fit the yoke's 56 mm gap. Each flange takes two M3 brass heat-set inserts in 4.0 mm bores: one on the pivot axis and one 14 mm below it for the arc lock. Both bores have 9 mm thrust bosses and take M3x12 screws with washers. The flanges are 5 mm thick so the bosses keep the part 55.0 mm wide overall. Every point stays inside a 28 mm radius of the pivot.
Sensor Tilt Yoke
A U-bracket that carries the tilt pivot for the 'NEMA17 Geared Radar Scan Turret' kit. The 90 x 40 x 5 mm base bolts to the turntable's heat-set inserts with four M3x10 screws through 3.4 mm holes at ±18 x ±12 mm. Two 6 mm gusseted cheeks leave a 56 mm gap. Each cheek has a 3.4 mm pivot hole at z38 with a 9 mm washer boss, plus an R14 arc lock slot 3.4 mm wide that covers ±45° of tilt. The cradle is held with M3x12 screws and washers.
Turret Pan Turntable Disc
A 110 mm diameter, 6 mm thick rotating deck for the 'NEMA17 Geared Radar Scan Turret' kit. It bolts to the top of the 60T ring-gear hub with four M3x8 screws that sit in 3.4 mm counterbored holes on a 40 mm PCD. It carries the sensor tilt yoke on four M3 brass heat-set inserts in 4.0 mm bores at ±18 x ±12 mm. It also has a 12 mm cable pass-through, an 18 x 1 mm underside recess that clears the 8 mm rod end and the 608 inner race, six 20 mm lightening windows, and a 1.5 mm stiffening rim that helps resist warping.
20T Stepper Drive Pinion
A 20-tooth involute spur pinion for the 'NEMA17 Geared Radar Scan Turret' kit. It has module 1.5, a 20° pressure angle, a 30 mm pitch diameter, a 33 mm OD, an 8 mm face and 0.5 mm chamfered tooth tips. It drives the 60T ring gear 3:1 at a 60.25 mm centre distance. It fits the NEMA 17 5 mm shaft through a 5.25 mm bore. The 18 mm hub holds an M3 set screw and a captured M3 hex nut, and the screw bears on the shaft flat.
60T Twin-608 Turret Ring Gear
Pan output gear and bearing hub for the 'NEMA17 Geared Radar Scan Turret' kit. It has 60 involute teeth (module 1.5, 20° pressure angle, 90 mm pitch diameter, 93 mm OD, 8 mm face) and meshes 3:1 with the 20T stepper pinion. The 32 mm hub holds two 608 bearings (8 x 22 x 7 mm) in 22.05 mm pockets, so the gear turns on the fixed 8 mm pan rod. A 50 mm top flange has four M3 heat-set insert bores (4.0 x 6 mm) on a 40 mm PCD to bolt on the turntable with M3x8 screws.
Turret Deck Support Leg
A 55 mm tall, 18 x 18 mm support column for the 'NEMA17 Geared Radar Scan Turret' kit (print 4). It lifts the deck plate so the NEMA 17 underneath clears the bench. The top has a 4.0 x 8 mm bore for an M3 brass heat-set insert that takes the M3x12 deck screw. The 40 x 40 x 4 mm gusseted foot has two 4.5 mm holes for M4 or #8 wood screws into the bench.
Turret Base Deck Plate
This is the foundation plate of the NEMA17 Geared Radar Scan Turret kit. The 130 x 90 x 6 mm deck holds a NEMA 17 stepper underneath on 31 mm square slots with ±1 mm of travel to set the gear mesh. It also carries the fixed 8 mm x 44 mm pan rod in a 20 mm boss, locked by an M3 heat-set set screw, with an 11 mm shoulder that supports the inner race of a 608 bearing. It bolts to four legs with M3x12 screws at (±56, ±36) and has lightening windows to save plastic.
Carriage Clevis Output Tower
This clevis output is part of the 'NEMA17 Leadscrew Push-Pull Actuator' kit. Its 40 x 36 x 5 mm base bolts to the carriage top with four M3x10 screws. They go through 3.4 mm holes on the 20 x 20 mm MGN12H pattern, with 6.5 mm counterbores. Two gusseted ears stand 35 mm tall with an 8.4 mm gap and hold an M3x20 pin and a nyloc 28 mm up, across the actuator axis. The ears are 12 mm wide so that a hex key can reach all four screws.
LM8UU Twin-Rod Leadscrew Carriage
The moving carriage for the 'NEMA17 Leadscrew Push-Pull Actuator' kit. The 30 x 84 x 32 mm block takes two press-fit LM8UU bearings (15.05 mm pockets) on 8 mm rods set 60 mm apart, and a T8 flange nut that screws into four radial slots with M3x12 self-tapping screws. The top face has four M3 heat-set bores on a 20 x 20 mm pattern that mount the clevis output tower.