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.

9 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.

10 partspairs verified
HARDWARE

Metric Fasteners & Threaded Hardware Pack

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

6 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.

14 partspairs verified
ELECTRONICS PROTOTYPING

Arduino / ESP32 Prototyping Kit

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

13 partspairs verified
ROBOTICS

Robotic Arm + Gripper Kit

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

12 partspairs verified
CNC MACHINING

CNC Workholding & Tooling Kit

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

14 partspairs verified
HVAC / DUCTING

HVAC Ventilation Duct Assembly Kit

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

8 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.

16 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.

16 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.

8 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.

8 partspairs verified
AUTOMOTIVE & MOBILITY

1:10 RC Car Drivetrain & Suspension Kit

A 1:10 RC Car Drivetrain & Suspension Kit cluster covering related CAD components for Automotive & Mobility.

5 partspairs verified
ROBOTICS & MECHATRONICS

Arduino / ESP32 Prototyping Kit; CNC Workholding & Tooling Kit

A Arduino / ESP32 Prototyping Kit; CNC Workholding & Tooling Kit cluster covering related CAD components for Robotics & Mechatronics.

1 partpairs verified
MOTORS & POWER TRANSMISSION

Arduino / ESP32 Prototyping Kit; RC / Line-Follower Robot Chassis Kit

A Arduino / ESP32 Prototyping Kit; RC / Line-Follower Robot Chassis Kit cluster covering related CAD components for Motors & Power Transmission.

1 partpairs verified
HYDRAULICS & PNEUMATICS

Belt & Roller Conveyor Design Kit

A Belt & Roller Conveyor Design Kit cluster covering related CAD components for Hydraulics & Pneumatics.

9 partspairs verified
PUMPS & FLUID SYSTEMS

Centrifugal Pump & Motor Skid Kit

A Centrifugal Pump & Motor Skid Kit cluster covering related CAD components for Pumps & Fluid Systems.

8 partspairs verified
GENERAL ENGINEERING

Honda C-Series Engine Parts Pack

A Honda C-Series Engine Parts Pack cluster covering related CAD components for General Engineering.

4 partspairs verified
VALVES & FLOW CONTROL

Hydraulic / Pneumatic Pump & Valve Manifold Kit; Industrial Valve & Actuation Pack

A Hydraulic / Pneumatic Pump & Valve Manifold Kit; Industrial Valve & Actuation Pack cluster covering related CAD components for Valves & Flow Control.

1 partpairs verified
ENCLOSURES & PANELS

IP65/IP67 Electrical Enclosure & Control Panel Pack

A IP65/IP67 Electrical Enclosure & Control Panel Pack cluster covering related CAD components for Enclosures & Panels.

9 partspairs verified
GENERAL ENGINEERING

Industrial Gearmotor & Drive Kit

A Industrial Gearmotor & Drive Kit cluster covering related CAD components for General Engineering.

9 partspairs verified
VALVES & FLOW CONTROL

Industrial Valve & Actuation Pack

A Industrial Valve & Actuation Pack cluster covering related CAD components for Valves & Flow Control.

9 partspairs verified
PUMPS & FLUID SYSTEMS

Peristaltic / Dosing Pump Prototyping Kit

A Peristaltic / Dosing Pump Prototyping Kit cluster covering related CAD components for Pumps & Fluid Systems.

9 partspairs verified
ROBOTICS & MECHATRONICS

Raspberry Pi Case & Display Kit

A Raspberry Pi Case & Display Kit cluster covering related CAD components for Robotics & Mechatronics.

6 partspairs verified
ENGINES & POWERTRAIN

Superquadro Engine Internals Kit

A Superquadro Engine Internals Kit cluster covering related CAD components for Engines & Powertrain.

4 partspairs verified
PUMPS & FLUID SYSTEMS

Vacuum Pump System Pack

A Vacuum Pump System Pack cluster covering related CAD components for Pumps & Fluid Systems.

9 partspairs verified
10,000+ models2D drawings
Sort by:
Free
Lofted CAD Model Demonstrating SolidWorks Techniques
MACHINE DESIGN · LOFTING

Lofted CAD Model Demonstrating SolidWorks Techniques

.STEP
Free
Bollard 500B Type A Parametric Model for Industrial Applications
INDUSTRIAL DESIGN · BOLLARD 500B

Bollard 500B Type A Parametric Model for Industrial Applications

.STEP
Free
Steam Engine for Torpedo Boat Dryzki
MARINE · STEAM ENGINE

Steam Engine for Torpedo Boat Dryzki

.STEP
Free
Marine Tech UTV Stereo Head Unit with 3-Inch LCD Screen
MARINE · MARINE TECH UTV STEREO

Marine Tech UTV Stereo Head Unit with 3-Inch LCD Screen

.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
M5 Waterproof Underwater Motor for Marine Applications
MARINE · M5 MOTOR

M5 Waterproof Underwater Motor for Marine Applications

.STEP
Free
Chrome Hydraulic Filler Strainer Breather Cap Assembly
MACHINE DESIGN · STRAINER

Chrome Hydraulic Filler Strainer Breather Cap Assembly

.STEP
Free
Industrial Pipe Fittings Range DN32 to DN500
CONSTRUCTION · PIPE FITTINGS

Industrial Pipe Fittings Range DN32 to DN500

.STEP
Free
High-Performance 1.1m RC Aircraft Frame for 4250 Motor
AVIATION · RC AIRCRAFT FRAME

High-Performance 1.1m RC Aircraft Frame for 4250 Motor

.STEP
Free
Detailed 3D Model Components for CARF P-51 RC Mustang
AVIATION · CARF P-51

Detailed 3D Model Components for CARF P-51 RC Mustang

.STEP
Free
3D Model of Boeing 737 NG Aircraft Wing
AEROSPACE · BOEING 737 NG

3D Model of Boeing 737 NG Aircraft Wing

.STEP
Free
Generative Shape Design Model for Engineering Applications
MACHINE DESIGN · GENERATIVE SHAPE DESIGN

Generative Shape Design Model for Engineering Applications

.STEP
Free
Quad Motor Mount for Vibration Dampening with 16x16 Mounting Pattern
ROBOTICS · QUAD MOTOR MOUNT

Quad Motor Mount for Vibration Dampening with 16x16 Mounting Pattern

.STEP
Free
200mm x 50mm BLDC Motor for Ultralight Aircraft Applications
AEROSPACE · BLDC MOTOR

200mm x 50mm BLDC Motor for Ultralight Aircraft Applications

.STEP
Free
Light Aircraft Nose Landing Gear Assembly
AEROSPACE · NOSE LANDING GEAR

Light Aircraft Nose Landing Gear Assembly

.STEP
Free
Aircraft Remotorization Engineering Model
AVIATION · AIRCRAFT REMOTORIZATION

Aircraft Remotorization Engineering Model

.STEP
Free
Airline Rail with 20mm Holes and 2000mm Length
AVIATION · AIRLINE RAIL

Airline Rail with 20mm Holes and 2000mm Length

.STEP
Free
Replacement Fan Blade Design for 3D Printing
3D PRINTING · FAN BLADE

Replacement Fan Blade Design for 3D Printing

.STEP
Free
Industrial Step Component CAD Model
MACHINE DESIGN · INDUSTRIAL STEP COMPONENT

Industrial Step Component CAD Model

.STEP
Free
Cessna 172 and B737 Style Wing Design Tutorial Overview
AVIATION · CESSNA 172

Cessna 172 and B737 Style Wing Design Tutorial Overview

.STEP
Free
RC Sport Plane with Custom Nose Design
AVIATION · RC PLANE

RC Sport Plane with Custom Nose Design

.STEP
Free
Sheet Metal APU Exhaust Duct Assembly
AEROSPACE · SHEET METAL

Sheet Metal APU Exhaust Duct Assembly

.STEP
Free
3D CAD Model of Mechanical Component
MACHINE DESIGN · MECHANICAL COMPONENT

3D CAD Model of Mechanical Component

.STEP