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
Connection Part Design for Aerospace Applications
MACHINE DESIGN · CONNECTION PART

Connection Part Design for Aerospace Applications

.STEP
Free
Gruebler's Count 3D Mechanism Design Model for Durable Machines
AEROSPACE · LE F 111

Gruebler's Count 3D Mechanism Design Model for Durable Machines

.STEP
Free
Space Heavy Logistics Transport Model
AEROSPACE · SPACE HEAVY LOGISTICS TRANSPORT 1

Space Heavy Logistics Transport Model

.STEP
Free
Professional Drone Assembly Design
ROBOTICS · DRONE ASSEMBLY 6

Professional Drone Assembly Design

.STEP

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Free
Detailed Air Screw Model for Yak-52 Scale 1:72
AVIATION · AIR SCREW

Detailed Air Screw Model for Yak-52 Scale 1:72

.STEP
Free
Speedybee F4 V3 Flight Controller Model
ROBOTICS · SPEEDYBEE F4 V3 2

Speedybee F4 V3 Flight Controller Model

.STEP
Free
F450 Quadcopter for Crack Detection Tools - Research Overview
ROBOTICS · F450 QUADCOPTER

F450 Quadcopter for Crack Detection Tools - Research Overview

.STEP
Free
nRF9160 Feather Wireless Module - BLE PCB Module
ELECTRICAL · BLE NRF9160 FEATHER

nRF9160 Feather Wireless Module - BLE PCB Module

.STEP
Free
Modular Walking Rig System with Adaptive Legs for Rough Terrain
AEROSPACE · NASA COMPETITION ENTRY

Modular Walking Rig System with Adaptive Legs for Rough Terrain

.STEP
Free
Modular Autonomous Transport System for LOX Tank Logistics
AEROSPACE · SUPER HEAVY LOGISTICS TRANSPORT 1

Modular Autonomous Transport System for LOX Tank Logistics

.STEP
Free
Center Wheel Cover for Peugeot 505 GTI
AUTOMOTIVE · PEUGEOT 505GTI

Center Wheel Cover for Peugeot 505 GTI

.STEP
Free
Swarm Technology Units for Heavy Lifting on Moon and Mars
ROBOTICS · SHL SWARM HEAVY LIFTING 1

Swarm Technology Units for Heavy Lifting on Moon and Mars

.STEP
Free
Flight Simulator Trim Wheel with Fuel Selector and Cutoff - CAD Model
AVIATION · FLIGHT SIMULATOR

Flight Simulator Trim Wheel with Fuel Selector and Cutoff - CAD Model

.STEP
Free
Advanced Multi-Dimensional and Angular Movement Mechanism
ROBOTICS · MOON AND MARS MOVER NEW DEGINE 1

Advanced Multi-Dimensional and Angular Movement Mechanism

.STEP
Free
Foldable Robotic Carriers for Lifting Habitat Modules
MACHINE DESIGN · WEDGEMASTER 1

Foldable Robotic Carriers for Lifting Habitat Modules

.STEP
Free
Rugged System on Module with SD Card and eMMC Variants
ELECTRICAL · RUGGED SOM

Rugged System on Module with SD Card and eMMC Variants

.STEP
Free
Planetary Gearbox Driven Screw Assembly with Spring Actuation
MACHINE DESIGN · PLANETARY GEARBOX

Planetary Gearbox Driven Screw Assembly with Spring Actuation

.STEP
Free
Universal Habitat Module for Mars Colonization
ARCHITECTURE · UNIVERSAL HABITAT MODULE 4 3 1

Universal Habitat Module for Mars Colonization

.STEP
Free
Supersonic Delta Wing Aircraft with Advanced Omnivision System
3D PRINTING · MISTRAL 3

Supersonic Delta Wing Aircraft with Advanced Omnivision System

.STEP
Free
Delivery Robot Model for Efficient Logistics
ROBOTICS · DELIVERY ROBOT

Delivery Robot Model for Efficient Logistics

.STEP
Free
Lightweight and Rigid Quadcopter Drone Frame Design
ROBOTICS · DRONE QUADCOPTER FRAME

Lightweight and Rigid Quadcopter Drone Frame Design

.STEP
Free
CAN Hub-12 Module for Advanced Drone Flight Control Systems
MACHINE DESIGN · CAN HUB 12 1

CAN Hub-12 Module for Advanced Drone Flight Control Systems

.STEP