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.*
Print-In-Place Chebyshev Lambda Straight-Line Linkage
This is a print-in-place Chebyshev lambda linkage that prints as one assembly. It has a 12 mm crank, a 24 mm ground link, 30 mm follower and coupler links, and a 60 mm coupler arm. It turns rotation from a 5 mm motor shaft into a near-straight tip stroke of about 48 mm, which you can use for walker legs, pushers or plotter feeds. The base takes four M3 self-tap screws from below. The crank hub has a 5.3 mm shaft bore with an M3 set-screw window, and the tip has a 3.4 mm M3 hole for mounting a foot or pen.
8 mm Shaft Eccentric Sheave And Strap
A print-in-place eccentric sheave and strap that turns 8 mm shaft rotation into a 12 mm push-pull stroke. Use it to drive pumps, shaker tables, sieves or agitators. The 44 mm disc has an 8.3 mm bore set 6 mm off-centre, locked by an M3 heat-set set screw. It turns inside a captive 56 mm strap ring held by a 45° V-groove and bead. The strap's arm ends in an M4 clearance eye at 80 mm centres.
M3-Pivot Lazy Tongs Reacher Kit
A classic lazy-tongs scissor linkage, printed flat as one snap-off sprue: six 90 mm cross links, two serrated jaw links and two finger-ring handle links. Each pivot is a 3.4 mm hole on a 45 mm pitch, so it bolts together with M3 x 10 screws and nyloc nuts into a five-stage reacher that stretches about 300 mm. Use it to grab parts that fell behind the bench, or to build a scissor-extension arm.
608/624 Bearing Slider-Crank Connecting Rod
This connecting rod runs on bearings at both ends. It has 80 mm between centres, a press-fit 608 big end (22.05 mm pocket) for an 8 mm crank pin and a press-fit 624 small end (13.05 mm pocket) for a 4 mm wrist pin. It turns a crank or wiper motor into back-and-forth motion for pumps, shakers, feeders and pushers. Each bearing seats on a 1.5–3.5 mm floor lip that touches only the outer race, and the U-channel beam prints flat so the push-pull load runs along the layers.
M5 Threaded Rod Scissor Lab Jack
Snap-apart kit for a screw-driven scissor lift platform: a 92 x 56 mm base channel with end wall, a matching 92 x 56 mm top platform channel, four 82 mm arms on 72 mm pivot centres (two with 4.5 mm standoff bosses), a nut trunnion and an octagon knob. Assemble with ten M5 bolts (M5x16 to M5x25, nyloc nuts) through the 5.5 mm pivot holes and 5.6 mm slide slots, drop M5 nuts into the trunnion and knob pockets, and drive it with a 100 mm length of M5 threaded rod; turning the knob pulls the trunnion along the base and lifts the platform from about 40 mm to 90 mm for setting the height of a camera, microscope, laser or soldering work.
Slotted Awning Window Scissor Stay Arm
A replacement arm for the flat scissor-stay linkage inside older awning windows, where cracked OEM arms are no longer sold. It is a 158 x 18 x 6 mm bar with a fixed 5.5 mm M5 pivot hole and a raised thrust pad at one end. Two 5.5 mm wide slots let you set the other pivots where your old arm had them: the middle slot runs 52–78 mm from the pivot and the end slot runs 119–143 mm. Measure your old arm before ordering, then fit it with M5 bolts, washers and nylock nuts.
608 Pivot Whiffletree Load Equalizer Bar
A 134 mm whiffletree (balance beam) that pivots on a press-fit 608 bearing (22.05 mm pocket, 16 mm through-bore for an 8 mm bolt or rod). It splits one pull into two equal or ratioed pulls for twin cables or tendons, cart or sled traces, or two-point lifts. Three pairs of M4 clearance holes (4.5 mm) sit at 30, 45 and 60 mm from the pivot. Using matched holes gives a 1:1 split, and mixing them gives 1.5:1, 2:1 and other ratios.
608 Slotted-Arm 90° Bellcrank
A 90° bellcrank that pivots on a press-fit 608 bearing (22.05 mm pocket on an 8 mm bolt or pin). It turns a push-pull rod or cable pull through a right angle for things like remote gate latches, hidden cabinet releases, RC linkages and attic hatch pulls. Each 50 mm arm has a fixed M3 clearance hole at the tip and a 3.4 mm adjustment slot from 20 to 40 mm, so you can change the throw and lever ratio without reprinting.
Quick-Return Slotted Rocker Lever
A 159 mm Whitworth-style quick-return rocker lever. One end has a 22.05 mm press-fit pocket for a 608 bearing as the pivot. The 13.4 mm wide, 80 mm long through-slot is sized for a 624 bearing (13 mm OD) on the crank pin to roll in. An M4 clearance eye at the far end connects to the output link. It turns a motor crank into a slow working stroke and a fast return stroke for shapers, wipers, kinetic sculptures and automata.
Slotted Tub Trip-Lever Linkage Extender
This slotted strap fits between a bathtub overflow trip lever and the plunger or rocker linkage below it. It adds length when the stock kit won't reach on a deep tub. The strap is 120 x 12 x 5 mm with a spine. One end has two 4.5 mm pin holes 10 mm apart, and the other end has a 52 mm long M4 slot, so with an M4 bolt and nylock the centre-to-centre reach can be set anywhere from 54 to 116 mm.
Door Lock Rod Lap Splice Coupler
A 50 x 18 x 14 mm splice block for a snapped car door lock or handle rod. The two broken ends slide into parallel 5.3 mm bores from opposite ends, overlap by 40 mm and are clamped by four M3 set screws in brass heat-set inserts. That fixes a door that won't lock or open from inside without buying a whole handle assembly. The bores take any round rod from about 3.5 to 5 mm, so it also joins mower, choke and throttle linkage rods.
Hip Horn Drive Link
Red 87 x 40 x 6 mm drive link for the 'SG90 Parallelogram-Leg Biped Walker' kit. A 40 mm horn pad holds an SG90 horn with two M2x10 self-tapping screws through 2.4 mm radial slots (r = 5–16 mm) around a 5.5 mm centre hole. 60.0 mm away, a 14 mm boss has a 3.4 mm hole for the M3x20 pivot screw and nyloc nut into the ankle lug. Print two and flip one for the other leg.
Horn-Side Drive Arm
A 5 mm thick, 98 mm long drive arm that bolts onto a hobby servo horn. A 2.4 mm radial slot running 6–22 mm from the pivot takes M2 horn screws at any horn hole spacing, and a 7 mm access hole sits over the spline screw. The far end has a pad with two M3 self-tap pilots (2.6 mm, 15 mm deep, 12 mm apart) that screw into the pad edge, so you can attach a linkage, gripper finger or flag.
Differential Cross-Pin Link
Link for the 'NEMA17 Rocker-Bogie Mars Rover Chassis' kit (print ×2). It has 40 mm between hole centres and joins the 625 differential bar end to the rocker ear. End A is a 12 mm OD × 6 mm eye with a vertical 3.4 mm hole. End B is a 10 × 12 × 12 mm boss with a 3.4 mm cross-hole along Y, 6 mm up. The two hole axes are perpendicular, so the link works as a cardan-style joint. Each end takes an M3x25 bolt with a nyloc nut and washers.
Flapper Wing Drive Link
This straight dog-bone link is part of the 'SG90 Scotch-Yoke Flapping Wing Rig' kit, and you print two. It is 46 x 9 x 4.4 mm, with 3.4 mm M3 clearance holes 37.0 mm apart in 9 mm bosses on an 8 mm wide, 4.0 mm stack. The lower end takes an M3x10 into the slider's heat-set insert. The upper end takes an M3x16 with a nyloc through the rocker. Each end has a 6.5 mm, 0.4 mm tall washer ring on opposite faces, so only the rings rub against the slider and the rocker. The whole stack is 4.4 mm and fits the 4.5 mm gap between them.
Snap-Socket Linkage Rod
A flat link, 87 x 17 x 8 mm, with two snap sockets 70 mm apart (centre to centre). Print ×3 for the 'SG90 3-DOF Ball-Balancing Platform' kit. Each Ø17 mm ring has a Ø8.6 mm bore with a Ø10.4 mm double-cone band in the middle and a 1.5 mm split slot, so it clips over the Ø10 mm ball studs on the SG90 Ball-Stud Crank Arm and the Tray Ball-Stud Knuckle without screws. PETG is recommended so the rings flex without cracking.
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.
Step Can Pedal Rocker Arm
Replacement rocker/bell-crank arm for the foot-pedal linkage in a step trash can (Simplehuman-style 30 L round cans and their clones), the one plastic lever that always snaps and that nobody sells as a service part. 98.7 mm long with a 5.5 mm pivot bore for a 5 mm pin or M5 bolt, two 4.5 mm pedal-rod holes 9 mm apart to re-tune pedal throw, and an open C-socket at the lift end that clips over a 4 mm lid rod; 10 mm tall bosses and a full-length spine rib carry the load in the print plane. Measure your can's pivot pin before printing — holes are sized to standard 4 mm / 5 mm pins.
Linked Vane Adjustable Air Louver
A print-in-place vane louver: four 23.5 mm vanes on a 25 mm pitch pivot on captive posts and are tied together by a slotted link bar, so one thumb tab sweeps all four together ±45° to aim or choke airflow. The 128 x 60 x 4 mm flange screws over a 102 x 46 mm panel cut-out with four 4.5 mm M4 clearance holes on a 114 x 46 mm pattern — for enclosure, cabinet, camper and fan-exhaust vents. Prints as one piece, six moving parts, 0.4 mm clearances throughout.
Print-In-Place Parallel Lift Lid Hinge
A print-in-place parallelogram four-bar hinge that lifts a box or tool-chest lid about 35 mm up and 35 mm back while holding it perfectly level, so the lid clears an overhanging rim or a wall behind the box. Overall 139 x 39 x 9 mm, with 35 mm links on 12 mm pivot spacing, four 4.0 mm pins running in 4.8 mm bores, and 5 mm mounting plates drilled 4.5 mm for M4 machine screws or #8 (4.2 mm shank) wood screws; print two and mount them as a pair on light lids.
Print-In-Place Pantograph Copier
A four-bar parallelogram pantograph that prints fully assembled in one piece — four bars on captive pin joints, no fasteners to add. Trace an original with an 8 mm stylus in the tracer socket and a pen in the output socket draws it at exactly 2:1 scale; both 8.3 mm sockets take an 8 mm rod or pen barrel and have M3 self-tapping pinch screws. The fulcrum eye takes an M4 screw to anchor it to the bench. Overall 169 x 68 x 19 mm.
608 Joint Robot Arm Link
A 132 mm U-channel arm link with a press-fit 608 bearing pocket (22.05 mm bore, 7.5 mm deep, stepped to a 16 mm clear bore) at each end on 100 mm centres, so two 8 mm shafts or M8 bolts give you a stiff, low-friction structural member for a small robot arm or four-bar linkage. The 4 mm floor carries a 20 × 20 mm M3 clearance pattern (MGN12H carriage or accessory bracket) and both 3 mm webs have 12 × 4 mm zip-tie slots for harness routing; overall 132 × 32 × 15 mm, ~33 cm³.