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
Super Heavy Logistic Transportation Monster Truck 1 | Professional CAD Design
AUTOMOTIVE · SUPER HEAVY LOGISTIC TRANSPORTATION MONSTER TRUCK 1

Super Heavy Logistic Transportation Monster Truck 1 | Professional CAD Design

.STEP
Free
Rocket Plug 107 Mm 1 | Professional CAD Design
AEROSPACE · ROCKET PLUG

Rocket Plug 107 Mm 1 | Professional CAD Design

.STEP
Free
Speedybee Bt Nano 3 1 | Professional CAD Design
ROBOTICS · SPEEDYBEE BT NANO 3 1

Speedybee Bt Nano 3 1 | Professional CAD Design

.STEP
Free
Radiomaster Rp3 Elrs Rx 1 | Professional CAD Design
ROBOTICS · RADIOMASTER RP3

Radiomaster Rp3 Elrs Rx 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
Nasa Foam 1 | Professional CAD Design
AEROSPACE · NASA FOAM 1

Nasa Foam 1 | Professional CAD Design

.STEP
Free
Trenz Microchip Smartfusion2 Soc Fpga Module 1 | Professional CAD Design
ELECTRICAL · SMARTFUSION2

Trenz Microchip Smartfusion2 Soc Fpga Module 1 | Professional CAD Design

.STEP
Free
Clamp 524 | Professional CAD Design
MACHINE DESIGN · CLAMP 524

Clamp 524 | Professional CAD Design

.STEP
Free
Le S Inspired Q400 Main Landing Gear 1 | Professional CAD Design
AVIATION · Q400

Le S Inspired Q400 Main Landing Gear 1 | Professional CAD Design

.STEP
Free
Vibro 3 | Professional CAD Design
MACHINE DESIGN · VIBRO 3

Vibro 3 | Professional CAD Design

.STEP
Free
T Motor 805 Coaxial Mounts 1 | Professional CAD Design
ROBOTICS · T MOTOR 805

T Motor 805 Coaxial Mounts 1 | Professional CAD Design

.STEP
Free
Tesla Roadster 6 | Professional CAD Design
AUTOMOTIVE · TESLA ROADSTER 6

Tesla Roadster 6 | Professional CAD Design

.STEP
Free
8 3 4 | Professional CAD Design
MACHINE DESIGN · 8 3 4

8 3 4 | Professional CAD Design

.STEP
Free
Digilent Arty Z7 Xilinx Artix 7 Soc Fpga Board 1 | Professional CAD Design
ELECTRICAL · DIGILENT ARTY Z7

Digilent Arty Z7 Xilinx Artix 7 Soc Fpga Board 1 | Professional CAD Design

.STEP
Free
Lockhead Martin F35A 1 | Professional CAD Design
AVIATION · LOCKHEED MARTIN F35A

Lockhead Martin F35A 1 | Professional CAD Design

.STEP
Free
Nasa Magnet 1 | Professional CAD Design
AEROSPACE · NASA MAGNET 1

Nasa Magnet 1 | Professional CAD Design

.STEP
Free
Hinge Based Clamping System 1 | Professional CAD Design
MACHINE DESIGN · HINGE BASED CLAMPING SYSTEM 1

Hinge Based Clamping System 1 | Professional CAD Design

.STEP
Free
Uav 125 | Professional CAD Design
AEROSPACE · UAV 125

Uav 125 | Professional CAD Design

.STEP
Free
Nasa Ring 1 | Professional CAD Design
AEROSPACE · NASA RING 1

Nasa Ring 1 | Professional CAD Design

.STEP
Free
Just Tork 1 | Professional CAD Design
MACHINE DESIGN · JUST TORK 1

Just Tork 1 | Professional CAD Design

.STEP
Free
Spring Mechanism 4 | Professional CAD Design
MACHINE DESIGN · SPRING MECHANISM 4

Spring Mechanism 4 | Professional CAD Design

.STEP
Free
Aviation Turbine Pump Impeller Blades 1 | Professional CAD Design
AVIATION · TURBINE

Aviation Turbine Pump Impeller Blades 1 | Professional CAD Design

.STEP
Free
Ball Hook Fastener 1 | Professional CAD Design
MACHINE DESIGN · BALL HOOK FASTENER 1

Ball Hook Fastener 1 | Professional CAD Design

.STEP