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.

Browse by part & function

The axis engineers actually search on — pick a part type to filter the catalog.

See all parts

Build kits

Curated systems with verified mating parts — download the whole assembly at once.

All collections
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
10,000+ models2D drawings
Sort by:
Free
Rs40 Chain 1 | 3D CAD Engineering Model
MACHINE DESIGN · RS40 CHAIN 1

Rs40 Chain 1 | 3D CAD Engineering Model

.STEP
Free
Raspberry Pi 4 With Powerpack Box 1 | 3D CAD Engineering Model
INDUSTRIAL DESIGN · RASPBERRY PI 4

Raspberry Pi 4 With Powerpack Box 1 | 3D CAD Engineering Model

.STEP
Free
Omni 136 Mm 1 | 3D CAD Engineering Model
3D PRINTING · OMNI 136 MM 1

Omni 136 Mm 1 | 3D CAD Engineering Model

.STEP
Free
Wheel Chair 61 | 3D CAD Engineering Model
MEDICAL · WHEEL CHAIR 61

Wheel Chair 61 | 3D CAD Engineering Model

.STEP

Need a CAD file that is not in the library?

Share your requirement and Marathon OS will match you with a vetted CAD designer for production-ready CAD files, edits and manufacturing documentation.

Get it Built
500+Projects Done
24 hrResponse
15+CAD Tools
Free
Amflow E30 400 Dc Motor 1 | 3D CAD Engineering Model
MACHINE DESIGN · AMFLOW E30 400 DC MOTOR

Amflow E30 400 Dc Motor 1 | 3D CAD Engineering Model

.STEP
Free
Huskylens 3 | 3D CAD Engineering Model
ROBOTICS · HUSKYLENS 3

Huskylens 3 | 3D CAD Engineering Model

.STEP
Free
Encoder 7 | 3D CAD Engineering Model
MACHINE DESIGN · ENCODER 7

Encoder 7 | 3D CAD Engineering Model

.STEP
Free
Peter Bar 3Lb Combat Robot Kit 1 | 3D CAD Engineering Model
ROBOTICS · PETER BAR 3LB

Peter Bar 3Lb Combat Robot Kit 1 | 3D CAD Engineering Model

.STEP
Free
Lrs 150 24 2 | 3D CAD Engineering Model
ELECTRICAL · LRS 150 24 2

Lrs 150 24 2 | 3D CAD Engineering Model

.STEP
Free
Lefs16B 300Nk S5C5185 Electric Actuator 1 | 3D CAD Engineering Model
MACHINE DESIGN · ELECTRIC ACTUATOR

Lefs16B 300Nk S5C5185 Electric Actuator 1 | 3D CAD Engineering Model

.STEP
Free
Bilboard Alpha 1 0 1 | 3D CAD Engineering Model
ARCHITECTURE · BILBOARD ALPHA 1 0 1

Bilboard Alpha 1 0 1 | 3D CAD Engineering Model

.STEP
Free
Arduino Nano 34 | 3D CAD Engineering Model
ELECTRICAL · ARDUINO NANO 34

Arduino Nano 34 | 3D CAD Engineering Model

.STEP
Free
Cup Griping Mechanism 1 | 3D CAD Engineering Model
MACHINE DESIGN · CUP GRIPING MECHANISM 1

Cup Griping Mechanism 1 | 3D CAD Engineering Model

.STEP
Free
Industrial Robotic Arm 13 | 3D CAD Engineering Model
ROBOTICS · INDUSTRIAL ROBOTIC ARM 13

Industrial Robotic Arm 13 | 3D CAD Engineering Model

.STEP
Free
Servo 100W Sigma V 1 | 3D CAD Engineering Model
ROBOTICS · SERVO 100W SIGMA V 1

Servo 100W Sigma V 1 | 3D CAD Engineering Model

.STEP
Free
Shuffler Pod Not Functional 1 | 3D CAD Engineering Model
3D PRINTING · SHUFFLER POD NOT FUNCTIONAL 1

Shuffler Pod Not Functional 1 | 3D CAD Engineering Model

.STEP
Free
Treedix Pico Pico W Pcb Breakout Board 1 | 3D CAD Engineering Model
ELECTRICAL · TREEDIX PICO PICO W

Treedix Pico Pico W Pcb Breakout Board 1 | 3D CAD Engineering Model

.STEP
Free
Hexapod Version B1 1 | 3D CAD Engineering Model
ROBOTICS · HEXAPOD VERSION B1 1

Hexapod Version B1 1 | 3D CAD Engineering Model

.STEP
Free
Laptop Back Cover Auto Screwing Machine Angle Screwing 1 | 3D CAD Engineering Model
MACHINE DESIGN · AUTO SCREWING MACHINE

Laptop Back Cover Auto Screwing Machine Angle Screwing 1 | 3D CAD Engineering Model

.STEP
Free
Gear Box For Pet Strip Cutter 1 | 3D CAD Engineering Model
MACHINE DESIGN · GEARBOX

Gear Box For Pet Strip Cutter 1 | 3D CAD Engineering Model

.STEP
Free
Motor 775 2 | 3D CAD Engineering Model
MACHINE DESIGN · MOTOR 775 2

Motor 775 2 | 3D CAD Engineering Model

.STEP
Free
Cycloidal Drive 12 | 3D CAD Engineering Model
MACHINE DESIGN · CYCLOIDAL DRIVE 12

Cycloidal Drive 12 | 3D CAD Engineering Model

.STEP