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
10,000+ models2D drawings
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Free
Pressure-Fed Liquid Fuel Engine with 30KN Thrust
AEROSPACE · PRESSURE-FED ENGINE

Pressure-Fed Liquid Fuel Engine with 30KN Thrust

.STEP
Free
PLA Grinding Mill 3D Printed Model
INDUSTRIAL DESIGN · PLA GRINDING MILL

PLA Grinding Mill 3D Printed Model

.STEP
Free
Cubesat Thermal and Structural Analysis Model
AEROSPACE · CUBESAT

Cubesat Thermal and Structural Analysis Model

.STEP
Free
100 Liter Capacity Drilling Machine Component
MACHINE DESIGN · DRILLING MACHINE

100 Liter Capacity Drilling Machine Component

.STEP

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Free
E-flite EFLG330 Tricycle 25-46 Landing Gear Set CAD Model
AVIATION · EFLG330

E-flite EFLG330 Tricycle 25-46 Landing Gear Set CAD Model

.STEP
Free
Servo Ball Screw Slide for Drilling and Tapping Machines
MACHINE DESIGN · SERVO BALL SCREW

Servo Ball Screw Slide for Drilling and Tapping Machines

.STEP
Free
Industrial Mechanical Component CAD Model
MACHINE DESIGN · MECHANICAL COMPONENT

Industrial Mechanical Component CAD Model

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

Industrial Step Component CAD Model

.STEP
Free
LHB Coach Prototype Model for Rail Transport
AUTOMOTIVE · LHB COACH

LHB Coach Prototype Model for Rail Transport

.STEP
Free
1/3 Scale Tank Cap Model for RC Pitts Special S1S Aircraft
AVIATION · TANK CAP

1/3 Scale Tank Cap Model for RC Pitts Special S1S Aircraft

.STEP
Free
Cowling for 1/3 Scale Pitts Special S1S Model Kit
AVIATION · COWLING

Cowling for 1/3 Scale Pitts Special S1S Model Kit

.STEP
Free
Simple Logistic Delivery Drone Design
ROBOTICS · LOGISTIC DRONE

Simple Logistic Delivery Drone Design

.STEP
Free
Precision Mechanical Component CAD Model
MACHINE DESIGN · PRECISION COMPONENT

Precision Mechanical Component CAD Model

.STEP
Free
Delivery Logistic Quadcopter Design for Efficient Transport
ROBOTICS · QUADCOPTER

Delivery Logistic Quadcopter Design for Efficient Transport

.STEP
Free
Seed Ball Dispenser for Drone Applications
ROBOTICS · SEED BALL DISPENSER

Seed Ball Dispenser for Drone Applications

.STEP
Free
Switchcraft IP66/IP68 Bulkhead Connector for Industrial Applications
ELECTRICAL · SWITCHCRAFT

Switchcraft IP66/IP68 Bulkhead Connector for Industrial Applications

.STEP
Free
HJT 16 Kiran Mk2 Aircraft 3D Model
AVIATION · HJT 16 KIRAN MK2

HJT 16 Kiran Mk2 Aircraft 3D Model

.STEP
Free
UAV Aircraft Model for Engineering and Design
AEROSPACE · UAV

UAV Aircraft Model for Engineering and Design

.STEP
Free
Rajdhani Express Train Model with EOG, 2AC, and 3AC Coaches
RAJDHANI EXPRESS

Rajdhani Express Train Model with EOG, 2AC, and 3AC Coaches

.STEP
Free
Detailed Orenda Engine Assembly Model
AEROSPACE · ORENDA ENGINE

Detailed Orenda Engine Assembly Model

.STEP
Free
Detailed Hydraulic Power Pack Model for Industrial Machinery
MACHINE DESIGN · HYDRAULIC POWER PACK

Detailed Hydraulic Power Pack Model for Industrial Machinery

.STEP
Free
Industrial Mechanical Component
MACHINE DESIGN · MECHANICAL COMPONENT

Industrial Mechanical Component

.STEP