Engineering CAD Design Library

Browse quality-checked 3D CAD models for engineering, product design, prototyping and manufacturing. Preview models online and download files in STEP, STP, IGES, STL, OBJ, PLY, DWG, DXF and more.

Browse by part & function

The axis engineers actually search on — pick a part type to filter the catalog.

See all parts

Build kits

Curated systems with verified mating parts — download the whole assembly at once.

All collections
CONSUMER ELECTRONICS

iPhone Accessory & Case Design Kit

A practical iPhone accessory cluster for designing cases, charging stands, holders and fit-checking around real phone geometry.

6 partspairs verified
DRONES / UAV

250 mm FPV Drone Build Kit

A complete FPV quad build cluster covering frame, propulsion, camera, control electronics, battery housing and mounting hardware.

7 partspairs verified
MOTION CONTROL

NEMA 17 Motion / Linear Actuator Kit

A motion-control cluster around a NEMA 17 stepper, bracket, coupler, GT2 belt, pulley, bearing and driver.

5 partspairs verified
HARDWARE

Metric Fasteners & Threaded Hardware Pack

A reusable ISO/metric fastener library cluster with screws, nuts, washers, inserts, standoffs and bolt assemblies.

2 partspairs verified
3D PRINTING

3D Printer Motion & Extruder Upgrade Kit

A 3D-printer upgrade cluster combining hotend parts, filament handling, stepper drive and motion hardware.

7 partspairs verified
ELECTRONICS PROTOTYPING

Arduino / ESP32 Prototyping Kit

A maker electronics cluster with Arduino, ESP32, breadboard, shield, servo, battery holder and enclosure.

7 partspairs verified
ROBOTICS

Robotic Arm + Gripper Kit

A robotic manipulator cluster with 6-DOF arm, gripper, wrist, servo mounts, actuator and linear guide components.

7 partspairs verified
CNC MACHINING

CNC Workholding & Tooling Kit

A CNC machining cluster covering table, clamping, vise, chuck, collet holder, spindle and ball-screw motion.

6 partspairs verified
HVAC / DUCTING

HVAC Ventilation Duct Assembly Kit

A ventilation product cluster with grille, damper, duct adapter, fan, filter, flange and duct clamp.

6 partspairs verified
FLUID POWER

Hydraulic / Pneumatic Pump & Valve Manifold Kit

A fluid-power cluster combining pump, valves, pressure gauge, manifold block, pipe and coupling parts.

8 partspairs verified
MOBILE ROBOTICS

RC / Line-Follower Robot Chassis Kit

A small mobile-robot cluster with chassis, wheels, hubs, motors, motor mounts, controller, battery holder and damper.

9 partspairs verified
WORKSPACE ACCESSORIES

Desk Cable + Phone Stand Workstation Kit

A desk-organization product cluster combining cable routing, phone holders, headphone stands and laptop/iMac stands.

7 partspairs verified
CAMERA / IMAGING RIGS

Camera Gimbal & Mount Rig Kit

A camera-rig cluster with gimbal, camera modules, tripod, tilt head, GoPro mount and camera bracket parts.

5 partspairs verified
10,000+ models2D drawings
Sort by:
Free
Automotibve Stud 1 | 3D CAD Engineering Model
AUTOMOTIVE · AUTOMOTIBVE STUD 1

Automotibve Stud 1 | 3D CAD Engineering Model

.STEP
Free
Part Model 40 | 3D CAD Engineering Model
MACHINE DESIGN · PART MODEL 40

Part Model 40 | 3D CAD Engineering Model

.STEP
Free
J Dion De Dion Axle Setup From Toyota Hilux Holds | 3D CAD Engineering Model
AUTOMOTIVE · DE DION AXLE

J Dion De Dion Axle Setup From Toyota Hilux Holds | 3D CAD Engineering Model

.STEP
Free
Tesla Ldu Rotor Shaft Spline 1 | 3D CAD Engineering Model
AUTOMOTIVE · TESLA

Tesla Ldu Rotor Shaft Spline 1 | 3D CAD Engineering Model

.STEP

Need a CAD file that is not in the library?

Share your requirement and Marathon OS will match you with a vetted CAD designer for production-ready CAD files, edits and manufacturing documentation.

Get it Built
500+Projects Done
24 hrResponse
15+CAD Tools
Free
Feed Pump Crank Shaft Bearing Housing Driver S Seat Floor | 3D CAD Engineering Model
MACHINE DESIGN · FEED PUMP

Feed Pump Crank Shaft Bearing Housing Driver S Seat Floor | 3D CAD Engineering Model

.STEP
Free
1743 | 3D CAD Engineering Model
MACHINE DESIGN · ENGINEERING VISUALIZATION

1743 | 3D CAD Engineering Model

.STEP
Free
Tools Box 8 | 3D CAD Engineering Model
INDUSTRIAL DESIGN · TOOLS BOX 8

Tools Box 8 | 3D CAD Engineering Model

.STEP
Free
Chain 41 | 3D CAD Engineering Model
MACHINE DESIGN · CHAIN 41

Chain 41 | 3D CAD Engineering Model

.STEP
Free
Lamborghini Wheel Rim 7 | 3D CAD Engineering Model
AUTOMOTIVE · LAMBORGHINI

Lamborghini Wheel Rim 7 | 3D CAD Engineering Model

.STEP
Free
Xu10J4Rs Camshaft 1 | 3D CAD Engineering Model
AUTOMOTIVE · XU10J4RS

Xu10J4Rs Camshaft 1 | 3D CAD Engineering Model

.STEP
Free
Cf Assy Fender 1 | 3D CAD Engineering Model
AUTOMOTIVE · CF ASSY FENDER 1

Cf Assy Fender 1 | 3D CAD Engineering Model

.STEP
Free
Westinghouse Assembly 1 | 3D CAD Engineering Model
ENERGY AND POWER · WESTINGHOUSE ASSEMBLY 1

Westinghouse Assembly 1 | 3D CAD Engineering Model

.STEP
Free
Fardriver Nd72680 1 | 3D CAD Engineering Model
MACHINE DESIGN · FARDRIVER ND72680 1

Fardriver Nd72680 1 | 3D CAD Engineering Model

.STEP
Free
Kmli Chassis Agni 1 | 3D CAD Engineering Model
AUTOMOTIVE · KMLI CHASSIS AGNI 1

Kmli Chassis Agni 1 | 3D CAD Engineering Model

.STEP
Free
Optimus Prime 5 | 3D CAD Engineering Model
ROBOTICS · OPTIMUS PRIME 5

Optimus Prime 5 | 3D CAD Engineering Model

.STEP
Free
Ironless Uc Linear Motor 1 | 3D CAD Engineering Model
MACHINE DESIGN · IRONLESS UC LINEAR MOTOR

Ironless Uc Linear Motor 1 | 3D CAD Engineering Model

.STEP
Free
Tyer And Wheel 1 | 3D CAD Engineering Model
AUTOMOTIVE · TYER AND WHEEL 1

Tyer And Wheel 1 | 3D CAD Engineering Model

.STEP
Free
Seat 2 1 1 | 3D CAD Engineering Model
AUTOMOTIVE · SEAT 2 1 1

Seat 2 1 1 | 3D CAD Engineering Model

.STEP
Free
Trike Cycle 1 | 3D CAD Engineering Model
AUTOMOTIVE · TRIKE CYCLE 1

Trike Cycle 1 | 3D CAD Engineering Model

.STEP
Free
Knuckle Joint 541 | 3D CAD Engineering Model
MACHINE DESIGN · KNUCKLE JOINT 541

Knuckle Joint 541 | 3D CAD Engineering Model

.STEP
Free
Pneumatic Drum Brake 1 | 3D CAD Engineering Model
AUTOMOTIVE · PNEUMATIC DRUM BRAKE

Pneumatic Drum Brake 1 | 3D CAD Engineering Model

.STEP
Free
Bearing Bracket 5 | 3D CAD Engineering Model
MACHINE DESIGN · BEARING BRACKET 5

Bearing Bracket 5 | 3D CAD Engineering Model

.STEP