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
Multi-Tool Organizer with Labeled Slots for Hand Tools and Drivers
INDUSTRIAL DESIGN · MULTI-TOOL ORGANIZER

Multi-Tool Organizer with Labeled Slots for Hand Tools and Drivers

.STEP
Free
Automotive Part Model for Reliable Vehicle Performance
AUTOMOTIVE · AUTOMOTIVE PART

Automotive Part Model for Reliable Vehicle Performance

.STEP
Free
Soviet State Quality Mark Symbol for Industrial Certification
INDUSTRIAL DESIGN · SOVIET STATE QUALITY MARK

Soviet State Quality Mark Symbol for Industrial Certification

.STEP
Free
BIGTREETECH TMC5160T Plus High-Power Stepper Motor Driver Module
ROBOTICS · BIGTREETECH TMC5160T PLUS

BIGTREETECH TMC5160T Plus High-Power Stepper Motor Driver Module

.STEP

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4x4 Matrix Keypad for Microcontroller Projects and Access Control
ELECTRICAL · 4X4 MATRIX KEYPAD

4x4 Matrix Keypad for Microcontroller Projects and Access Control

.STEP
Free
Universal Adjustable Marking Square for Precise Angle Setting
MACHINE DESIGN · UNIVERSAL ADJUSTABLE MARKING SQUARE

Universal Adjustable Marking Square for Precise Angle Setting

.STEP
Free
Industrial Belt Conveyor System for Material Handling
INDUSTRIAL DESIGN · BELT CONVEYOR

Industrial Belt Conveyor System for Material Handling

.STEP
Free
Laser Tree Dovetail Mount for CNC Laser Systems
3D PRINTING · LASER TREE DOVETAIL MOUNT

Laser Tree Dovetail Mount for CNC Laser Systems

.STEP
Free
Protective Case and Lid for Garmin Z82 Laser Rangefinder
GARMIN Z82

Protective Case and Lid for Garmin Z82 Laser Rangefinder

.STEP
Free
Automated Bottle Filling Machine Prototype with Conveyor and Pump System
MACHINE DESIGN · AUTOMATED BOTTLE FILLING MACHINE

Automated Bottle Filling Machine Prototype with Conveyor and Pump System

.STEP
Free
Differential Mechanism Swerve Drive for Dynamic Power Allocation
ROBOTICS · DIFFERENTIAL MECHANISM

Differential Mechanism Swerve Drive for Dynamic Power Allocation

.STEP
Free
3D Print-in-Place Fidget Rings with Stand for Prototyping
3D PRINTING · 3D PRINT-IN-PLACE

3D Print-in-Place Fidget Rings with Stand for Prototyping

.STEP
Free
Simple Mechanical Part Model for Engineering Applications
MACHINE DESIGN · MECHANICAL PART

Simple Mechanical Part Model for Engineering Applications

.STEP
Free
Alloy Steel Mechanical Component with Revolve Boss and Circular Pattern Features
MACHINE DESIGN · ALLOY STEEL

Alloy Steel Mechanical Component with Revolve Boss and Circular Pattern Features

.STEP
Free
Plain Carbon Steel Mechanical Part with Boss Extrude and Fillet Features
MACHINE DESIGN · PLAIN CARBON STEEL

Plain Carbon Steel Mechanical Part with Boss Extrude and Fillet Features

.STEP
Free
CoreXY 3D Printer Frame with Hypercube Aluminum Profile
3D PRINTING · COREXY

CoreXY 3D Printer Frame with Hypercube Aluminum Profile

.STEP
Free
TNUT University Emblem 3D Model
TNUT UNIVERSITY EMBLEM

TNUT University Emblem 3D Model

.STEP
Free
USB Quick Charge Power Bank Circuit Board Assembly
ELECTRICAL · USB QUICK CHARGE

USB Quick Charge Power Bank Circuit Board Assembly

.STEP
Free
Thread-Clamping Smartphone Holder for Cortisol Strip
MEDICAL · THREAD-CLAMPING

Thread-Clamping Smartphone Holder for Cortisol Strip

.STEP
Free
Gyrobifastigium Johnson Solid Polyhedron Model
GYROBIFASTIGIUM

Gyrobifastigium Johnson Solid Polyhedron Model

.STEP
Free
Automizer 22mm Vaping Component CAD Model
INDUSTRIAL DESIGN · AUTOMIZER 22MM

Automizer 22mm Vaping Component CAD Model

.STEP
Free
Alloy Steel Mechanical Part with Advanced Features for High-Strength Applications
MACHINE DESIGN · ALLOY STEEL

Alloy Steel Mechanical Part with Advanced Features for High-Strength Applications

.STEP