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
Autonomous Indoor Security Quadcopter 1 | Professional CAD Design
ROBOTICS · AUTONOMOUS

Autonomous Indoor Security Quadcopter 1 | Professional CAD Design

.STEP
Free
Tbs Crossfire Nano Rx Antenna 1 | Professional CAD Design
ROBOTICS · TBS CROSSFIRE NANO RX ANTENNA 1

Tbs Crossfire Nano Rx Antenna 1 | Professional CAD Design

.STEP
Free
Jetcat P100 Rx Stock Nozzle 1 | Professional CAD Design
AVIATION · JETCAT P100-RX

Jetcat P100 Rx Stock Nozzle 1 | Professional CAD Design

.STEP
Free
Airplane Body 1 | Professional CAD Design
AVIATION · AIRPLANE BODY 1

Airplane Body 1 | Professional CAD Design

.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
Thin Square Tube With Fem Solid Beam Contact Analysis 1 | Professional CAD Design
MACHINE DESIGN · THIN SQUARE TUBE

Thin Square Tube With Fem Solid Beam Contact Analysis 1 | Professional CAD Design

.STEP
Free
Ulm Trike 1 | Professional CAD Design
AUTOMOTIVE · ULM TRIKE 1

Ulm Trike 1 | Professional CAD Design

.STEP
Free
Hirth 3202 1 | Professional CAD Design
MACHINE DESIGN · HIRTH 3202 1

Hirth 3202 1 | Professional CAD Design

.STEP
Free
Innovation New Materials 2 | Professional CAD Design
INDUSTRIAL DESIGN · INNOVATION NEW MATERIALS 2

Innovation New Materials 2 | Professional CAD Design

.STEP
Free
Sgmjv 2 | Professional CAD Design
MACHINE DESIGN · SGMJV 2

Sgmjv 2 | Professional CAD Design

.STEP
Free
Sawyer Avion Cohete Ueao No Tripulado 1 | Professional CAD Design
AVIATION · SAWYER AVION COHETE UEAO NO TRIPULADO 1

Sawyer Avion Cohete Ueao No Tripulado 1 | Professional CAD Design

.STEP
Free
Hunter 50 H50 Predator Helicopter Drone Uav 1 | Professional CAD Design
AVIATION · HUNTER 50

Hunter 50 H50 Predator Helicopter Drone Uav 1 | Professional CAD Design

.STEP
Free
Safe Panel Release Let It Go 1 | Professional CAD Design
MACHINE DESIGN · SAFE PANEL RELEASE LET IT GO 1

Safe Panel Release Let It Go 1 | Professional CAD Design

.STEP
Free
Dij Phantom 3 1 | Professional CAD Design
ROBOTICS · DIJ PHANTOM 3 1

Dij Phantom 3 1 | Professional CAD Design

.STEP
Free
Sinalizador Vermelho 1 | Professional CAD Design
INDUSTRIAL DESIGN · SINALIZADOR VERMELHO 1

Sinalizador Vermelho 1 | Professional CAD Design

.STEP
Free
Swerve Drive Bk Robotics 1 | Professional CAD Design
ROBOTICS · SWERVE DRIVE

Swerve Drive Bk Robotics 1 | Professional CAD Design

.STEP
Free
Jurassic Rc Jet 1 | Professional CAD Design
AVIATION · JURASSIC RC JET 1

Jurassic Rc Jet 1 | Professional CAD Design

.STEP
Free
Servo Holder Kavan Go 1053Mg Go 1269Mgw 1 | Professional CAD Design
ROBOTICS · SERVO HOLDER

Servo Holder Kavan Go 1053Mg Go 1269Mgw 1 | Professional CAD Design

.STEP
Free
Holybro X500 V2 Arm 1 | Professional CAD Design
ROBOTICS · HOLYBRO X500 V2

Holybro X500 V2 Arm 1 | Professional CAD Design

.STEP
Free
Holybro Fixed Carbon Fiber Gps Mount 2 1 | Professional CAD Design
ROBOTICS · HOLYBRO FIXED CARBON FIBER GPS MOUNT 2.1

Holybro Fixed Carbon Fiber Gps Mount 2 1 | Professional CAD Design

.STEP
Free
T Motor Q1418 Propeller Adapter 1 | Professional CAD Design
AVIATION · T MOTOR Q1418

T Motor Q1418 Propeller Adapter 1 | Professional CAD Design

.STEP
Free
Ti 6Al 4V Alpha And Beta Hcp Bcc Crystal Structures | Professional CAD Design
INDUSTRIAL DESIGN · TI6AL4V

Ti 6Al 4V Alpha And Beta Hcp Bcc Crystal Structures | Professional CAD Design

.STEP
Free
Australian Ca 23 Fighter Concept Solid Assembly Model 1 | Professional CAD Design
AVIATION · AUSTRALIAN CA 23

Australian Ca 23 Fighter Concept Solid Assembly Model 1 | Professional CAD Design

.STEP