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
Toy Ship 1 | 3D CAD Engineering Model
MARINE · TOY SHIP 1

Toy Ship 1 | 3D CAD Engineering Model

.STEP
Free
Housing 38 | 3D CAD Engineering Model
MACHINE DESIGN · HOUSING 38

Housing 38 | 3D CAD Engineering Model

.STEP
Free
Fd 26 Power 1 | 3D CAD Engineering Model
ENERGY AND POWER · FD 26 POWER 1

Fd 26 Power 1 | 3D CAD Engineering Model

.STEP
Free
Stuffing Box 38 | 3D CAD Engineering Model
MACHINE DESIGN · STUFFING BOX 38

Stuffing Box 38 | 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
Anchor 31 | 3D CAD Engineering Model
MARINE · ANCHOR 31

Anchor 31 | 3D CAD Engineering Model

.STEP
Free
Model Ship 3 | 3D CAD Engineering Model
MARINE · MODEL SHIP 3

Model Ship 3 | 3D CAD Engineering Model

.STEP
Free
8 Ft Container 1 | 3D CAD Engineering Model
INDUSTRIAL DESIGN · 8 FT CONTAINER 1

8 Ft Container 1 | 3D CAD Engineering Model

.STEP
Free
Eqmar Watermaker Ro 120 L H 1 | 3D CAD Engineering Model
MARINE · EQMAR WATERMAKER RO 120 L H 1

Eqmar Watermaker Ro 120 L H 1 | 3D CAD Engineering Model

.STEP
Free
Luz Perko Pk 1044 Dp1 Blk 1 | 3D CAD Engineering Model
INDUSTRIAL DESIGN · LUZ PERKO PK 1044 DP1 BLK 1

Luz Perko Pk 1044 Dp1 Blk 1 | 3D CAD Engineering Model

.STEP
Free
36 1 Crankshaft Efi Trigger Wheel 1 | 3D CAD Engineering Model
AUTOMOTIVE · CRANKSHAFT

36 1 Crankshaft Efi Trigger Wheel 1 | 3D CAD Engineering Model

.STEP
Free
Single Axle Cannon 1 | 3D CAD Engineering Model
MACHINE DESIGN · SINGLE AXLE CANNON 1

Single Axle Cannon 1 | 3D CAD Engineering Model

.STEP
Free
Hand Reel Scuba Diving 1 | 3D CAD Engineering Model
MARINE · HAND REEL

Hand Reel Scuba Diving 1 | 3D CAD Engineering Model

.STEP
Free
Hydrofoil Propeller 4 Variations Request 1 | 3D CAD Engineering Model
MARINE · HYDROFOIL

Hydrofoil Propeller 4 Variations Request 1 | 3D CAD Engineering Model

.STEP
Free
Double Wishbone 5 | 3D CAD Engineering Model
AUTOMOTIVE · DOUBLE WISHBONE

Double Wishbone 5 | 3D CAD Engineering Model

.STEP
Free
10Ft High Cube Shipping Container 1 | 3D CAD Engineering Model
CONSTRUCTION · 10FT HIGH CUBE SHIPPING CONTAINER

10Ft High Cube Shipping Container 1 | 3D CAD Engineering Model

.STEP
Free
Airbus Challenge Gear Pump 1 | 3D CAD Engineering Model
AEROSPACE · GEAR PUMP

Airbus Challenge Gear Pump 1 | 3D CAD Engineering Model

.STEP
Free
Soviet Navy Uniform 1 | 3D CAD Engineering Model
SOVIET NAVY UNIFORM 1

Soviet Navy Uniform 1 | 3D CAD Engineering Model

.STEP
Free
A1500 Alum Boat 1 | 3D CAD Engineering Model
MARINE · A1500 ALUM BOAT 1

A1500 Alum Boat 1 | 3D CAD Engineering Model

.STEP
Free
Damen Stan Tender 1905 1 | 3D CAD Engineering Model
MARINE · DAMEN STAN TENDER 1905

Damen Stan Tender 1905 1 | 3D CAD Engineering Model

.STEP
Free
Gopro Mask Mount 1 | 3D CAD Engineering Model
3D PRINTING · GOPRO MASK MOUNT 1

Gopro Mask Mount 1 | 3D CAD Engineering Model

.STEP
Free
3D Instalacao Do Sensor 1 | 3D CAD Engineering Model
MACHINE DESIGN · 3D INSTALACAO DO SENSOR 1

3D Instalacao Do Sensor 1 | 3D CAD Engineering Model

.STEP
Free
Whio Yacht Cruiser 1 | 3D CAD Engineering Model
MARINE · WHIO YACHT CRUISER 1

Whio Yacht Cruiser 1 | 3D CAD Engineering Model

.STEP