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
Simple Support Leg for Unhitched Trailer
AUTOMOTIVE · SUPPORT LEG

Simple Support Leg for Unhitched Trailer

.STEP
Free
Suspension System Engineering Model for Vehicle Dynamics
AUTOMOTIVE · SUSPENSION SYSTEM

Suspension System Engineering Model for Vehicle Dynamics

.STEP
Free
Slide Out Steps for MB Sprinter Truck Rear Access
AUTOMOTIVE · SLIDE OUT STEPS

Slide Out Steps for MB Sprinter Truck Rear Access

.STEP
Free
V6 Engine Valve Cover CAD Model
AUTOMOTIVE · V6 ENGINE

V6 Engine Valve Cover CAD Model

.STEP

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Free
Mini DC/DC Step-Up Voltage Module 5V to 12V Compact Size
ELECTRICAL · DC-DC CONVERTER

Mini DC/DC Step-Up Voltage Module 5V to 12V Compact Size

.STEP
Free
CNC Threading Boring Bar for Precision Machining
MACHINE DESIGN · CNC

CNC Threading Boring Bar for Precision Machining

.STEP
Free
Connecting Rod for Automotive Engine Applications
AUTOMOTIVE · CONNECTING ROD

Connecting Rod for Automotive Engine Applications

.STEP
Free
Spacer Intermediate Plate for 2.0 TDI Engine
AUTOMOTIVE · SPACER INTERMEDIATE PLATE

Spacer Intermediate Plate for 2.0 TDI Engine

.STEP
Free
Car Engine Piston Head CAD Model
AUTOMOTIVE · PISTON HEAD

Car Engine Piston Head CAD Model

.STEP
Free
Universal Drive Shaft Coupler for Mechanical Systems
MACHINE DESIGN · UNIVERSAL DRIVE SHAFT COUPLER

Universal Drive Shaft Coupler for Mechanical Systems

.STEP
Free
Detailed 3D Model of Formula E Gen 3 Race Car
AUTOMOTIVE · FORMULA E GEN 3

Detailed 3D Model of Formula E Gen 3 Race Car

.STEP
Free
TP 50 Torx Socket with 3/8 Inch Drive for Ford F-150 Bolts
AUTOMOTIVE · TP 50 TORX SOCKET

TP 50 Torx Socket with 3/8 Inch Drive for Ford F-150 Bolts

.STEP
Free
6-Cylinder Engine Assembly Model
AUTOMOTIVE · 6-CYLINDER ENGINE

6-Cylinder Engine Assembly Model

.STEP
Free
Carbon Fiber Car Wheel Design for Automotive Applications
AUTOMOTIVE · CARBON FIBER

Carbon Fiber Car Wheel Design for Automotive Applications

.STEP
Free
High-Performance Car Engineering Overview
AUTOMOTIVE · HIGH-PERFORMANCE CAR

High-Performance Car Engineering Overview

.STEP
Free
M12-1.75 x 120mm Flanged Button Head Bed Bolt for Ford F-150
AUTOMOTIVE · M12-1.75X120MM

M12-1.75 x 120mm Flanged Button Head Bed Bolt for Ford F-150

.STEP
Free
Detailed 3D Model of a 4-Cylinder Inline Engine
AUTOMOTIVE · 4 CYLINDER ENGINE

Detailed 3D Model of a 4-Cylinder Inline Engine

.STEP
Free
LED Headlight Mounting Assembly for Twizy
AUTOMOTIVE · LED HEADLIGHT MOUNTING

LED Headlight Mounting Assembly for Twizy

.STEP
Free
Connecting Rod Mechanical Component CAD Model
MACHINE DESIGN · CONNECTING ROD

Connecting Rod Mechanical Component CAD Model

.STEP
Free
Intricate Car Wheel Design for Automotive Applications
AUTOMOTIVE · CAR WHEEL

Intricate Car Wheel Design for Automotive Applications

.STEP
Free
Rail Profiles Compliant with AS1085.1-2002 Standards
CONSTRUCTION · RAIL PROFILES

Rail Profiles Compliant with AS1085.1-2002 Standards

.STEP
Free
115RE R8 and 136RE TR68 Industrial Components
MACHINE DESIGN · 115RE R8

115RE R8 and 136RE TR68 Industrial Components

.STEP