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
22mm Red TN2 Automotive Switch with Lamp, Type 1NO1NC
AUTOMOTIVE · 22MM SWITCH

22mm Red TN2 Automotive Switch with Lamp, Type 1NO1NC

.STEP
Free
Dot Matrix Display Module for Arduino Projects
ELECTRICAL · DOT MATRIX DISPLAY

Dot Matrix Display Module for Arduino Projects

.STEP
Free
Precision Measurement Device CAD Model
INDUSTRIAL DESIGN · PRECISION MEASUREMENT

Precision Measurement Device CAD Model

.STEP
Free
4.6x2.2mm Momentary Push Button Switch Model
ELECTRICAL · MOMENTARY PUSH BUTTON SWITCH

4.6x2.2mm Momentary Push Button Switch 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
4 Inch Exhaust Fan for PC and Refrigerator Cooling
ELECTRICAL · EXHAUST FAN

4 Inch Exhaust Fan for PC and Refrigerator Cooling

.STEP
Free
Vacuum Pump Assembly for Industrial Applications
INDUSTRIAL DESIGN · VACUUM PUMP

Vacuum Pump Assembly for Industrial Applications

.STEP
Free
Inline Wire Joiner for Electrical Connections 600V 32A Capacity
ELECTRICAL · INLINE WIRE JOINER

Inline Wire Joiner for Electrical Connections 600V 32A Capacity

.STEP
Free
Single Cell Holder for 21700 Battery
ELECTRICAL · 21700 BATTERY

Single Cell Holder for 21700 Battery

.STEP
Free
Three-Phase Circuit Breaker PDC11F160TAENN Industrial Model
ELECTRICAL · THREE-PHASE CIRCUIT BREAKER

Three-Phase Circuit Breaker PDC11F160TAENN Industrial Model

.STEP
Free
5.5kW Cylindrical Gear Motor from Mitsubishi Electric DM-DP Series
MACHINE DESIGN · 5.5KW

5.5kW Cylindrical Gear Motor from Mitsubishi Electric DM-DP Series

.STEP
Free
21.5mm Precision Bearing for Mechanical Applications
MACHINE DESIGN · 21.5MM BEARING

21.5mm Precision Bearing for Mechanical Applications

.STEP
Free
Adapter with 1/4 Inch Male and 1/8 Inch Female Pipe Threads
INDUSTRIAL DESIGN · PIPE ADAPTER

Adapter with 1/4 Inch Male and 1/8 Inch Female Pipe Threads

.STEP
Free
1/8 Inch Male Pipe Thread Connector with 7/16 Inch Hex and 1/4 Inch ID Bore
INDUSTRIAL DESIGN · PIPE THREAD CONNECTOR

1/8 Inch Male Pipe Thread Connector with 7/16 Inch Hex and 1/4 Inch ID Bore

.STEP
Free
Lab Control Panel Component for Industrial Applications
INDUSTRIAL DESIGN · LAB CONTROL PANEL

Lab Control Panel Component for Industrial Applications

.STEP
Free
SR T5 Contactor by Mitsubishi Electric
ELECTRICAL · SR T5

SR T5 Contactor by Mitsubishi Electric

.STEP
Free
Push Button Switch CAD Model for Industrial Applications
ELECTRICAL · PUSH BUTTON SWITCH

Push Button Switch CAD Model for Industrial Applications

.STEP
Free
Double Contactor S-T10 with Reverse Switching and Thermal Relay TH-T18
ELECTRICAL · DOUBLE CONTACTOR

Double Contactor S-T10 with Reverse Switching and Thermal Relay TH-T18

.STEP
Free
7.5kW Cylindrical Gear Motor from Mitsubishi Electric DM-DP Series
MACHINE DESIGN · 7.5KW

7.5kW Cylindrical Gear Motor from Mitsubishi Electric DM-DP Series

.STEP
Free
SMA 2-Hole Panel Mount Connector for Secure RF Connections
ELECTRICAL · SMA CONNECTOR

SMA 2-Hole Panel Mount Connector for Secure RF Connections

.STEP
Free
Electric Linear Actuator Axmo TMF3-050 Industrial Model
MACHINE DESIGN · ELECTRIC LINEAR ACTUATOR

Electric Linear Actuator Axmo TMF3-050 Industrial Model

.STEP
Free
Electrical Cabinet Mounting Lock
ELECTRICAL · ELECTRICAL CABINET

Electrical Cabinet Mounting Lock

.STEP
Free
Mitsubishi Electric S-T25 BC Contactor Industrial Component
ELECTRICAL · MITSUBISHI ELECTRIC

Mitsubishi Electric S-T25 BC Contactor Industrial Component

.STEP