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.

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

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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
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Free
Detailed Distillation Tower Model with Stress Analysis for Oil and Gas Refinery
CHEMICAL · DISTILLATION TOWER

Detailed Distillation Tower Model with Stress Analysis for Oil and Gas Refinery

.STEP
Free
Double American-Style Electrical Outlet with Grounding Pin
ELECTRICAL · DOUBLE ELECTRICAL OUTLET

Double American-Style Electrical Outlet with Grounding Pin

.STEP
Free
Aluminum DIN Rail 35mm Wide for Electrical Component Mounting
ELECTRICAL · DIN RAIL

Aluminum DIN Rail 35mm Wide for Electrical Component Mounting

.STEP
Free
Brass Step Down Fitting with 1/2" to 1/4" Male NPT Threads
INDUSTRIAL DESIGN · BRASS STEP DOWN FITTING

Brass Step Down Fitting with 1/2" to 1/4" Male NPT Threads

.STEP

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Engineering Study Analysis 5
MACHINE DESIGN · ENGINEERING STUDY

Engineering Study Analysis 5

.STEP
Free
3/8 Inch Offset Hanging Bracket for 1 Inch Aluminum Extrusions
MACHINE DESIGN · OFFSET HANGING BRACKET

3/8 Inch Offset Hanging Bracket for 1 Inch Aluminum Extrusions

.STEP
Free
AFAG IRG1MS Actuator Control Panel
INDUSTRIAL DESIGN · AFAG IRG1MS

AFAG IRG1MS Actuator Control Panel

.STEP
Free
Professional Engineering Designs Collection
MACHINE DESIGN · ENGINEERING DESIGN

Professional Engineering Designs Collection

.STEP
Free
Industrial Ventilator Model Reference 33562
INDUSTRIAL DESIGN · INDUSTRIAL VENTILATOR

Industrial Ventilator Model Reference 33562

.STEP
Free
Engineering Study Model 9
MACHINE DESIGN · ENGINEERING STUDY MODEL 9

Engineering Study Model 9

.STEP
Free
Smart Street Light with Integrated Camera, Motion Sensor, and Cooling System
ELECTRICAL · SMART STREET LIGHT

Smart Street Light with Integrated Camera, Motion Sensor, and Cooling System

.STEP
Free
Post-Touch Lathe Chuck Drawing
MACHINE DESIGN · LATHE CHUCK

Post-Touch Lathe Chuck Drawing

.STEP
Free
Hydraulic Filter Component for Fluid Systems
MACHINE DESIGN · HYDRAULIC FILTER

Hydraulic Filter Component for Fluid Systems

.STEP
Free
3D Model of a DC Motor for Engineering Applications
MACHINE DESIGN · DC MOTOR

3D Model of a DC Motor for Engineering Applications

.STEP
Free
Heat Transfer Unit for Water Heating Applications
ENERGY AND POWER · HEAT TRANSFER UNIT

Heat Transfer Unit for Water Heating Applications

.STEP
Free
Dual Refrigerant Circle Water Chiller with Heat Reclaim System
ENERGY AND POWER · DUAL REFRIGERANT CIRCUIT

Dual Refrigerant Circle Water Chiller with Heat Reclaim System

.STEP
Free
5-Inch Square Cooling Fan with Quick-Disconnect Terminals, 200-240V AC
ELECTRICAL · COOLING FAN

5-Inch Square Cooling Fan with Quick-Disconnect Terminals, 200-240V AC

.STEP
Free
6-Position Fused Power Distribution Strip with DIN Rail Mount
ELECTRICAL · 6-POSITION POWER DISTRIBUTION STRIP

6-Position Fused Power Distribution Strip with DIN Rail Mount

.STEP
Free
DROK DC-DC Constant Voltage and Current Converter 5-65V to 0-60V
ELECTRICAL · DC-DC CONVERTER

DROK DC-DC Constant Voltage and Current Converter 5-65V to 0-60V

.STEP
Free
Push Button Reset Circuit Breaker with Spade Tab Connections 5A
ELECTRICAL · PUSH BUTTON RESET

Push Button Reset Circuit Breaker with Spade Tab Connections 5A

.STEP
Free
High-Speed Fan Generator CAD Model
ENERGY AND POWER · HIGH-SPEED FAN GENERATOR

High-Speed Fan Generator CAD Model

.STEP
Free
Industrial Heat Exchanger Design for Thermal Applications
ENERGY AND POWER · HEAT EXCHANGER

Industrial Heat Exchanger Design for Thermal Applications

.STEP