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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Build kits

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
9989 models2D drawings
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Free
iNRCORE MIL-STD-1553 Single Bus Communications Transformer Model
ELECTRICAL · INRCORE MIL STD 1553 TRANSFORMER

iNRCORE MIL-STD-1553 Single Bus Communications Transformer Model

.STEP
Free
iNRCORE Dual MIL-STD-1553 Bus Communications Transformer Model
ELECTRICAL · MIL-STD-1553

iNRCORE Dual MIL-STD-1553 Bus Communications Transformer Model

.STEP
Free
iNRCORE MIL-STD-1553 Single Bus Communications Transformer Model
ELECTRICAL · INRCORE MIL STD 1553 TRANSFORMER

iNRCORE MIL-STD-1553 Single Bus Communications Transformer Model

.STEP
Free
Super Heavy Logistics Transport Concept for Lunar and Martian Missions
ROBOTICS · SHLT WALKING BEAN 1

Super Heavy Logistics Transport Concept for Lunar and Martian Missions

.STEP

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Free
Super Heavy Logistics Transporter with Mecanum Wheels and Scissors Lift Mechanism
AUTOMOTIVE · SUPER HEAVY LOGISTICS TRANSPORTER 1

Super Heavy Logistics Transporter with Mecanum Wheels and Scissors Lift Mechanism

.STEP
Free
Four Way Electrical Conduit Joint Box with Dual Access Points
AVIATION · AVIONICS

Four Way Electrical Conduit Joint Box with Dual Access Points

.STEP
Free
Carby V3 Starship Enterprise High Power Rocket CAD Model
AEROSPACE · CARBY V3

Carby V3 Starship Enterprise High Power Rocket CAD Model

.STEP
Free
Ababil 3 UAV - Unmanned Aerial Vehicle Model
AVIATION · ABABIL 3 UAV

Ababil 3 UAV - Unmanned Aerial Vehicle Model

.STEP
Free
Children's Educational Rocket Model for Learning Projects
AEROSPACE · ROCKET 189

Children's Educational Rocket Model for Learning Projects

.STEP
Free
Cloud Dancer II Model Aircraft CAD Design
AEROSPACE · CLOUD DANCER II 1

Cloud Dancer II Model Aircraft CAD Design

.STEP
Free
Comet Captain Future Model for Enthusiasts and Collectors
ROBOTICS · COMET CAPTAIN FUTURE 1

Comet Captain Future Model for Enthusiasts and Collectors

.STEP
Free
Detailed Jet Engine Assembly Model
AEROSPACE · JET ENGINE

Detailed Jet Engine Assembly Model

.STEP
Free
Off-Road Vehicle Concept for Heavy Load Transport on Moon and Mars
AUTOMOTIVE · TRANSPORT CONCEPT

Off-Road Vehicle Concept for Heavy Load Transport on Moon and Mars

.STEP
Free
Unmanned Aerial Vehicle (UAV) 3D Model
AVIATION · UAV 124

Unmanned Aerial Vehicle (UAV) 3D Model

.STEP
Free
DCH-5 Buffalo 3D Model for Engineering and Design
MACHINE DESIGN · DCH 5 BUFFALO 1

DCH-5 Buffalo 3D Model for Engineering and Design

.STEP
Free
Toroidal Propeller Design for Advanced Engineering Applications
AEROSPACE · TOROIDAL PROPELLER 11

Toroidal Propeller Design for Advanced Engineering Applications

.STEP
Free
Flying Car Protective Wing Cover Design
AUTOMOTIVE · FLYING CAR 14

Flying Car Protective Wing Cover Design

.STEP
Free
Detailed Helicopter Rotor CAD Model
MACHINE DESIGN · ROTOR 109

Detailed Helicopter Rotor CAD Model

.STEP
Free
Aviation Dashboard Instrument Panel with Temperature and Speed Gauges
AVIATION · AVIATION DASHBOARD

Aviation Dashboard Instrument Panel with Temperature and Speed Gauges

.STEP
Free
Structural Stability Model for Heavy Logistics Transport
AEROSPACE · SUPER HEAVY LOGISTICS TRANSPORT

Structural Stability Model for Heavy Logistics Transport

.STEP
Free
SHL Lunar Surface Track Model
AUTOMOTIVE · SHL TRANSPORT 1

SHL Lunar Surface Track Model

.STEP
Free
Lemon DSMP Transmitter Module DIY Version CAD Model
3D PRINTING · LEMON DSMP DIY MODULE 1

Lemon DSMP Transmitter Module DIY Version CAD Model

.STEP