Free
structural engineering CAD Models
Browse structural engineering CAD models used in real projects. Preview online and download STEP/STP, IGES, STL and more. Filter by category, file type, price and popularity.
Browse by part & function
The axis engineers actually search on — pick a part type to filter the catalog.
Build kits
Curated systems with verified mating parts — download the whole assembly at once.
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.
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.
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.
HARDWARE
Metric Fasteners & Threaded Hardware Pack
A reusable ISO/metric fastener library cluster with screws, nuts, washers, inserts, standoffs and bolt assemblies.
3D PRINTING
3D Printer Motion & Extruder Upgrade Kit
A 3D-printer upgrade cluster combining hotend parts, filament handling, stepper drive and motion hardware.
ELECTRONICS PROTOTYPING
Arduino / ESP32 Prototyping Kit
A maker electronics cluster with Arduino, ESP32, breadboard, shield, servo, battery holder and enclosure.
ROBOTICS
Robotic Arm + Gripper Kit
A robotic manipulator cluster with 6-DOF arm, gripper, wrist, servo mounts, actuator and linear guide components.
CNC MACHINING
CNC Workholding & Tooling Kit
A CNC machining cluster covering table, clamping, vise, chuck, collet holder, spindle and ball-screw motion.
HVAC / DUCTING
HVAC Ventilation Duct Assembly Kit
A ventilation product cluster with grille, damper, duct adapter, fan, filter, flange and duct clamp.
FLUID POWER
Hydraulic / Pneumatic Pump & Valve Manifold Kit
A fluid-power cluster combining pump, valves, pressure gauge, manifold block, pipe and coupling parts.
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.
WORKSPACE ACCESSORIES
Desk Cable + Phone Stand Workstation Kit
A desk-organization product cluster combining cable routing, phone holders, headphone stands and laptop/iMac stands.
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.
AUTOMOTIVE & MOBILITY
1:10 RC Car Drivetrain & Suspension Kit
A 1:10 RC Car Drivetrain & Suspension Kit cluster covering related CAD components for Automotive & Mobility.
ROBOTICS & MECHATRONICS
Arduino / ESP32 Prototyping Kit; CNC Workholding & Tooling Kit
A Arduino / ESP32 Prototyping Kit; CNC Workholding & Tooling Kit cluster covering related CAD components for Robotics & Mechatronics.
MOTORS & POWER TRANSMISSION
Arduino / ESP32 Prototyping Kit; RC / Line-Follower Robot Chassis Kit
A Arduino / ESP32 Prototyping Kit; RC / Line-Follower Robot Chassis Kit cluster covering related CAD components for Motors & Power Transmission.
HYDRAULICS & PNEUMATICS
Belt & Roller Conveyor Design Kit
A Belt & Roller Conveyor Design Kit cluster covering related CAD components for Hydraulics & Pneumatics.
PUMPS & FLUID SYSTEMS
Centrifugal Pump & Motor Skid Kit
A Centrifugal Pump & Motor Skid Kit cluster covering related CAD components for Pumps & Fluid Systems.
GENERAL ENGINEERING
Honda C-Series Engine Parts Pack
A Honda C-Series Engine Parts Pack cluster covering related CAD components for General Engineering.
VALVES & FLOW CONTROL
Hydraulic / Pneumatic Pump & Valve Manifold Kit; Industrial Valve & Actuation Pack
A Hydraulic / Pneumatic Pump & Valve Manifold Kit; Industrial Valve & Actuation Pack cluster covering related CAD components for Valves & Flow Control.
ENCLOSURES & PANELS
IP65/IP67 Electrical Enclosure & Control Panel Pack
A IP65/IP67 Electrical Enclosure & Control Panel Pack cluster covering related CAD components for Enclosures & Panels.
GENERAL ENGINEERING
Industrial Gearmotor & Drive Kit
A Industrial Gearmotor & Drive Kit cluster covering related CAD components for General Engineering.
VALVES & FLOW CONTROL
Industrial Valve & Actuation Pack
A Industrial Valve & Actuation Pack cluster covering related CAD components for Valves & Flow Control.
PUMPS & FLUID SYSTEMS
Peristaltic / Dosing Pump Prototyping Kit
A Peristaltic / Dosing Pump Prototyping Kit cluster covering related CAD components for Pumps & Fluid Systems.
ROBOTICS & MECHATRONICS
Raspberry Pi Case & Display Kit
A Raspberry Pi Case & Display Kit cluster covering related CAD components for Robotics & Mechatronics.
ENGINES & POWERTRAIN
Superquadro Engine Internals Kit
A Superquadro Engine Internals Kit cluster covering related CAD components for Engines & Powertrain.
PUMPS & FLUID SYSTEMS
Vacuum Pump System Pack
A Vacuum Pump System Pack cluster covering related CAD components for Pumps & Fluid Systems.
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