Print-ready 3D models

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.

8 mm Shaft Cycloidal-Rise Plate Cam

This is a plate cam (rise-and-fall disc) for an 8 mm shaft or rod. Over each turn it lifts a 624 roller follower (13 mm OD) by 20 mm and lowers it again, using a cycloidal motion profile so the follower starts and stops without jerk. The profile is offset for the roller's 6.5 mm radius, so the follower moves exactly 26 to 46 mm from the shaft axis. The disc is 8 mm thick and the hub is 22 mm in diameter. An 8.3 mm slip-fit bore and a radial M3 heat-set insert pocket (4.0 mm) for a set screw lock it to the shaft, which suits automata, pumps, stamping rigs and indexing demos.

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.

Desk Drawer 624 Roller Replacement Bracket

This screw-on roller bracket replaces a cracked nylon drawer wheel on older desks and dressers. It uses a 624 bearing (4 x 13 x 5 mm) on an M4 x 16 bolt, and an M4 nut sits in a pocket on the back so the cabinet side holds it captive. The flange is 60 x 19 x 4 mm. It has two 4 mm slots, 10 mm long, for #6 wood screws, so you can raise or lower the wheel to level a sagging drawer. A ribbed 12.5 mm boss holds the wheel 10 mm off the wall, and the wheel sticks out 3.5 mm past the flange edge for the runner to ride on.

Surface-Mount 624 Screen Door Roller

This roller replaces a discontinued roller on a sliding patio or storm screen door. A 56 x 27 x 5 mm plate screws to the inside face of the bottom rail with two #6 screws. The screws sit in 12 mm vertical slots, so you set the door height when you tighten them. The wheel is a 624 bearing (4 x 13 x 5 mm) held by an M4 x 14 screw threaded into an M4 heat-set insert. The insert presses into a 5.5 mm bore from the back of the plate. The bearing sits on a raised land that touches only its inner race, and it hangs 1.5 mm below the bottom of the plate so it runs on the track rib.

624 Roller Thrust Fork

A bolt-down fork that holds one 624 bearing (4 x 13 x 5 mm) on a radial M4x25 axle. It is part of the 'MG996R Heavy Pan-Tilt Camera Gimbal' kit, which uses three of them. The foot is 36 x 22 x 4 mm and fixes to the base deck's M3 heat-sets through two 3.4 mm holes 20 mm apart. The roller top sits 14 mm above the deck, and M3 washers under the foot raise it to 17 mm. The rollers carry the pan platter's weight, so the MG996R's spline doesn't have to.

Module 1.5 Winch Worm

This is the self-locking worm for the 'N20 Self-Locking Worm-Drive Winch' kit. It is a single-start, right-hand, module 1.5 worm: 15 mm OD, 12 mm pitch diameter, 4.712 mm lead and a 7.1° lead angle. It has a 16 x 10 mm collar with a 3.1 mm bore, 10 mm deep, for the N20 3 mm D-shaft, which an M3x8 grub screw and captured M3 nut hold. Its 4 mm tail pin runs in a 624 bearing (4 x 13 x 5 mm). The overall length is 39 mm, and it prints standing on the collar face.

N20 Worm Motor Sled

This motor sled is part of the 'N20 Self-Locking Worm-Drive Winch' kit. It holds an N20 gearmotor (12 x 10 mm gearbox, 3 mm D-shaft, fixed with two zip-ties) and a 624 tail bearing (4 x 13 x 5 mm, 13.05 mm press pocket) in line with the worm axis. It bolts to the base plate with three M3 heat-set inserts (4.0 mm bores) and M3x10 screws, and measures 22 x 95 x 24.5 mm. The middle insert bore goes through the floor because the floor under the worm is only 6 mm thick.

624 Bearing Front Wheel

A free-rolling Ø60 x 20 mm front wheel for the 'SG90 Ackermann Steering Rover Chassis' kit. It has two tyre grooves (3 x 1.5 mm, 5 mm in from each face) for O-rings or rubber bands. Each face has a Ø13.05 x 5.2 mm press-fit pocket for a 624 bearing (4 x 13 x 5 mm), and a Ø6 bore passes through the web for the knuckle's M4x30 axle bolt. Print two. It prints flat with no supports: a 4 mm floor web and six full-height spokes join the 3 mm rim to the Ø20 hub.

Seven-LED Lamp Head

This is the tilting head of the 'MG90S Animatronic Desk Lamp Robot' kit. It has a 70 mm shade with a 3 mm face that takes seven 5 mm LEDs through 5.3 mm holes, one in the centre and six on a 16 mm radius. The 32 mm-wide R14 tilt tongue sits with its axis 50 mm above the face. The side-A pad takes the MG90S/SG90 horn. Side B has a 4.5 mm M4 hole, an M4 nut pocket (7.2 mm across flats) and a 7 mm boss that runs on the Upper Arm's 624 bearing (4 x 13 x 5 mm). The pivot is an M4x16 bolt.

Upper Arm Channel Link

This is the elbow-to-head link of the 'MG90S Animatronic Desk Lamp Robot' kit. It is a 131 x 47 x 28 mm U-channel, printed web-down, with its joint axes 95 mm apart. The elbow tongue is 32 mm wide and takes the MG90S/SG90 horn on one side. On the other side it takes an M4x16 bolt, a captive M4 nut and a 7 mm boss that runs on a 624 bearing (4 x 13 x 5 mm). The head clevis is 36 mm wide. It has two M3 heat-set bores (4.0 mm) at a 44 mm pitch for the slotted servo plate, and a 13.05 mm press-fit seat for a 624 bearing.

Lower Arm Channel Link

Shoulder-to-elbow link for the 'MG90S Animatronic Desk Lamp Robot' kit. It is a 146 x 47 x 28 mm U-channel printed web-down. The 32 mm tongue takes the shoulder servo horn on one side and an M4x16 bolt, M4 nut and 624 bearing on the other. At the top end, a 36 mm elbow clevis has two M3 heat-set bores for the slotted MG90S/SG90 plate and a 13.05 mm press-fit seat for a 624 bearing (4 x 13 x 5 mm).

Turntable Shoulder Clevis

Yaw turntable for the 'MG90S Animatronic Desk Lamp Robot' kit. It is a 118 mm disc that rides on the Weighted Yaw Base Tub's thrust rim at r=54–60, centred by a 53.5 mm skirt. A 32 mm solid horn pad with a 7 mm screw-access hole takes the MG90S/SG90 yaw servo horn. The shoulder clevis sits 36 mm above the deck, with 36 mm between the cheeks. The servo cheek has M3 heat-set bores at a 44 mm pitch and a 34 × 16 mm body window for the slotted servo plate. The bearing cheek has a press-fit 624 seat, 13.05 × 5 mm, behind a 10 mm lip. The disc also has two 20 × 8 mm wire slots.

Horn-And-Bearing Joint Yoke

A C-shaped yoke for a robot arm joint. The top arm bolts to a servo horn (7 mm centre hole plus two 2.4 mm screw slots) and the bottom arm holds a 624 bearing (13 mm OD) press-fit on the same axis, so the servo is supported on both sides instead of hanging off its spline. The 5 mm back plate has four M3 clearance holes on a 16 x 20 mm pattern to mount the next arm link, and the part prints on its side so the joint loads run along the layers, not across them.

624 Bearing Tread Wheel

A 32 mm OD x 9 mm wide passive side wheel from the 'SG90 Wheeled Serpentine Snake Robot' kit. It has a 13.05 mm press pocket, 5 mm deep, for a 624 bearing (4 x 13 x 5 mm), and a 4 mm outer web with a 10 mm through-hole so an M4x16 SHCS and washer can bear on the inner race. A 3 x 1.5 mm centred tread groove takes a rubber band or O-ring tyre for sideways grip.

Wheel Axle Bridge

A 16 x 36 x 11.5 mm black box-section axle bridge from the 'SG90 Wheeled Serpentine Snake Robot' kit. It bolts under each Servo Segment Housing floor with two M3x12 SHCS through 3.4 mm holes into the floor's M3 heat-set inserts. Each flat outer cheek at y = ±18 carries an 11 mm M4 heat-set boss with a 5.5 mm teardrop bore. That bore takes an M4x16 SHCS as the axle for a 624-bearing tread wheel. A bottom tie and a centre web stiffen the cheeks against wheel side-load, and relief pockets let a hex key reach the M3 screw heads.

Servo Segment Housing

Open-top body segment for the 'SG90 Wheeled Serpentine Snake Robot' kit. It measures 50 x 36 x 33 mm and holds an SG90 or MG90S servo on a z=33 tab seat. Four M3 heat-set pillars take the clamp frame, and a 16 x 20 mm M3 heat-set face bolts to the next yoke. It also has an M4 pivot slot for the 624-bearing joint bolt and two M3 heat-set floor bosses for the wheel axle bridge.

Twin 624 Track Idler Sprocket

The free-running front idler (print 2) for the 'N20 Twin-Track Mini Tank Chassis' kit. It has the same 12-tooth, 12 mm-pitch profile as the drive sprocket: a Ø46 x 10 mm disc with teeth reaching Ø51.2. Its 18 mm hub holds two 624 bearings (4 x 13 x 5 mm) in 13.05 mm press-fit seats, one at each end, with a 10 mm lip between them. The pair spins on the hull's slotted M4x30 bolt axle and stays stiffer and better aligned than a single-bearing idler.

Scotch-Yoke Wing Slider

This slider is part of the 'SG90 Scotch-Yoke Flapping Wing Rig' kit. It is a 56 x 26 x 10 mm block with a 40 x 13.5 mm round-ended through-slot. The crank's 624 bearing (4 x 13 x 5 mm) rolls in the slot and turns servo rotation into a ±13.5 mm vertical stroke. A 32 mm wide top tab holds two M3 heat-set inserts (4.0 mm bores, 8 mm deep) 20 mm apart, where the wing drive links bolt on. The 4 mm edge bands on both sides are left flat to slide between the frame pads and the retainer strips.

Servo Horn Scotch Crank

This is the crank for the 'SG90 Scotch-Yoke Flapping Wing Rig' kit. It's a 36 x 16 x 6 mm stadium bar with a sunken seat on the back for a single-arm SG90 horn: a 7.5 mm channel plus a 10 mm centre recess. A 6 mm centre hole gives screwdriver access to the horn screw. At the other end, 12 mm from the axis, a 9 mm boss carries a 624 bearing (4 x 13 x 5) on an M4x20 bolt, which sits in a 4.5 mm clearance bore with a captive M4 nut pocket on the back.

X Arm Tip Idler Roller

The far-end block for the 'NEMA17 Cantilever Pen Plotter' kit's X arm, about 54 x 57 x 74 mm. It clamps the ends of two 8 mm rods set 40 mm apart in 25 mm pinch sockets (M3x16 screw plus a captured M3 nut in each). Two cheeks hold a 608 bearing as the GT2 belt idler on an 8x25 mm dowel, locked by an M3x10 self-tap screw. Below, a fork carries a 624 bearing on an M4x20 axle in a height-adjustable slot, so the arm tip rolls on the desk and can be levelled. It prints upside down, standing on the flat tops of the cheeks and clamps.

5 mm Shaft Groove Cam For 624 Roller

A positive-drive face cam for a 5 mm motor shaft such as a NEMA 17. Its closed 13.6 mm groove holds a 624 bearing (13 mm OD) as the roller and drives it both ways, so the follower needs no return spring. Each turn gives a 15 mm cycloidal rise over 120°, a 60° dwell, a 120° return and a 60° dwell. The cam is about 92 × 107 mm, and an M3 set screw with a captured nut locks the hub to the shaft.

624 Roller Cam Follower Slide

A print-in-place linear cam follower: a 13 x 13.5 mm plunger rides with 0.5 mm clearance through a guide housing that bolts down with four M3 screws. The plunger's head takes a 624 bearing (4 x 13 x 5 mm) as a roller on an M4 bolt with a captive nut, and it has 14 mm of stroke. Band posts on the housing and plunger let a rubber band pull the roller against your cam.

Brake Line Roller Straightener Block

A five-roller straightening block for 3/16 in (4.76 mm) brake, fuel and copper-nickel line: three 624 bearings on the lower row and two offset above squeeze the tube to a 4.2 mm nip (0.56 mm set) so coiled line pulls through dead straight. 110 x 44 x 18 mm body with V-groove entry and exit guides, 3.4 mm self-tapping holes for M4x16 socket-head screws (the 7 mm head clamps only the bearing's inner race), and four 5.5 mm M5 holes to bolt it to the bench — or grip the 9 mm plate edges in a vise.

⚠ Flagged: hydraulic brake system. Not for safety-critical use without independent engineering review.