20+ Free 3D Models and Downloadable CAD Files of Mechanical and Engineering Designs


Free 3D models are a great way to start experimenting with CAD to see how it fits into your business. 3D modeling has become one of the most common methods to design products ranging from jets to tiny phone cameras and everything in between.

It’s particularly important in the field of engineering. Freelance engineering design services are responsible for making mechanical and other designs work. Their understanding of how machines work can help them build new engines, design better manufacturing machinery, and so much more.

Chances are if your product needs to move in some way, an engineer is needed. You don’t have to rush out and hire one right away, however. Cad Crowd has hundreds of free downloadable CAD files featuring mechanical and engineer designs from our freelancers. Here are just a few of these designs that you can download right now.

Six Axis Industrial Robotic Arm


This incredible school project features an industrial arm similar to those in production. The 3D model is complete with 121 different parts, including the fasteners, and even has a technical drawing sheet that could be used for manufacturing. This is one of the more detailed 3D models available for download and is a great opportunity to see how CAD design services work up close and personal.

Car Spoiler


This 3D model of a car spoiler comes with a lift, drag, and velocity analysis. The unique-looking model looks like it could be at home on any fast car. If you dream of speed and love the idea of reducing the drag on your future race car, this car spoiler is a great option that’s just a download away.

Jet Engine


This 3D model of a jet engine is incredibly beautiful and perfect as a mockup. While it doesn’t have all the small parts needed for assembly, there is a rough draft available to help give a detailed idea of what the engine might look like.

Mock-ups are useful for teaching, demonstrations, design evaluation, and so much more. While this jet engine isn’t flight ready yet, it may be perfect for your use.

Engine Assembly


This engine assembly shows a simple design that can be used as a base for your own experiments. If you’re curious about how an engine assembly works or are looking for a base to work off of, this may be a good choice.



This machine is used to heat plastic waste to temperatures that allow oil, gas, or kerosene to be recovered from plastic waste. This is a practical way to help reduce the waste of fossil fuels and to get something useful out of old scrap plastic.

As more people become concerned about the enormous amount of plastic waste, machinery such as this to help recycle scrap plastic and keep it out of the world’s oceans may be in high demand.

Rim Brake


This 3D model of a rim brake is so detailed that it looks like you could almost reach out and pick it up. Feel free to look at it as closely as you want with the free download.

Camera Model


This camera model has a unique look while still performing the job as a camera. The download comes with six files, including the stills shown. The bright colors and modern appearance are attractive and look like they could be part of a branded set. Imagine what a camera branded for your own company might look like.

CNC Machine


This downloadable file of a CNC machine has real dimensions, making it a useful model for those interested in manufacturing equipment.

Ventilator Tubing


Ventilator tubes are an in-demand item right now, with many countries struggling to be able to find enough medical equipment. This detailed 3D model shows an up-close look at a common part for a ventilator.

Models like this are particularly wonderful because they are potentially lifesaving. If ventilator tubing is needed for patients in a hospital, downloading this 3D model could be a step toward getting that person the care they need.

Candlelight PCB


This LED light is designed to flicker like a candle, making it a useful part for battery-operated candles. This particular model has five LED lights for the part, creating a vivid and breath-taking display to go with your electric candle.

Floating Solar Energy System


With global warming being a topic of rising concern, interest in clean energy is at an all-time high. This floating solar system improves efficiency by removing thermal drift and providing its own cooling system.

Elevator Buttons


High contact surfaces can spread disease by transferring bacteria and viruses onto your hands, and then into your body when you touch your face. These elevator buttons make it easier to avoid transferring germs onto your face by making it easy to touch the buttons with your elbow instead.

With the effects of COVID-19 likely to linger long after this year, installing buttons like these are practical steps toward safety.

Face Mask


If you don’t have your own face mask and find it difficult to get one due to the short supply, this 3D model of a face mask is 3D printable. The 3D modeling designer recommends painting the surfaces after printing them due to holes in the plastic.

Solar Power Converter


This detailed 3D model shows a solar power converter for microwatts (µW), It is designed for indoor IoT-devices and includes a backup battery. Solar power is becoming a popular form of green energy because it doesn’t produce greenhouse gases after its initial production, it’s free, and it’s renewable. Harness a little piece of that energy with your own solar power converter today.

Aircraft Wing


This sleek aircraft wing is an essential part to helping planes take flight. This 3D model isn’t just a pretty mockup, it has been tested under Fatigue and Airflow, for a load of 50000N. Although this is just one part of a complex aircraft, models like these are important for studying how planes go together and what they need for flight.

Car Exhaust Manifold


This 3D model goes the extra mile with detailed renderings that look incredibly realistic, the model itself, and a gif file showing a heat analysis. These added steps make it a great quality model.

Kitchen Sink


Engineering design services can be called on for an incredible variety of objects, and this kitchen sink is just one example. The simple yet sleek design would look at home in any modern house. Use this model to flesh out an interior design, or see what it looks like in your own home with this free 3D model.

Garden Swing


Everyone loves spending time in the great outdoors, especially young children. This garden swing is both beautiful and sturdy and would make a beautiful accent piece for the backyard.

Robotic Snake


This fun robot will delight and amaze children and adults alike. It also makes for an amazing and detailed 3D model, with seven separate sections to this engineering marvel. This is a very fun download for a variety of reasons, whether you want to try and build it yourself or just enjoy the fun and possibilities of this great model.

Radial Engine


This engine demonstration shows a common type of aviation engine. The well thought out design is perfect for helping you create a mockup of your own future plane.

Air Blower


This air blower has a sleek design, and comes not just with a 3D model but an analysis of the air flow. This helps in understanding how the product will work after production, an enormous step.

Graphics Card


This concept is a design based off of the RTX 2080Ti made by Nvidia. It shows many details of the real graphics card, and is an excellent 3D model available for download.



Even tiny variations in a bullet can make it less accurate. The bullets in the 3D rendering of this model are stunning, but more important is the analysis that comes with it. The analysis shows how the bullet might travel, an important part of this concept. The fewer errors in a bullet casing, the truer it will fly, which makes an analysis like this important.

Refractory Mixer


This mixer is designed to help mix refractory materials such as those used in ceramics, glassmaking, and similar arts. This 3D model is a prime example of the sheer variety of different tools needed for the many different trades out there.

Cad Crowd’s 3D Model Library Is at Your Disposal

These are just a few of the many different models available on Cad Crowd. No matter what industry you need a model for, the talented freelancers at Cad Crowd are constantly coming up with new ways to put their talents to use. Check out the models in the library.

Many of the models they make are on Cad Crowd for free, so feel free to browse these products and pick something for free today. If you don’t see something you like, you can also contact a designer for your own custom model.