How to bring CNC Machines into the Classroom Safely

Summary

In the modern Makerspace learning environment, we are challenging young makers, creators, and innovators to bring their ideas to life through prototyping and problem solving. CNC Machines, like 3D printers, lasers, and mills are real-world rapid-prototyping machines that are phenomenal tools to bring into the education space, and in this article we look at how this can be done safely.

1. Considering the Different Types of CNC Machines

CNC stands for computer numerical control, and this describes a machine which is controlled by a computer based on a coordinate system. CNC machines are not new, and have been around since the 1950's, but modern CNC machines typically found in a makerspace consist of 3D printers, laser cutters and engravers, and milling machines like the Carvera and Carvera Air.

Each of these machines allows you to manufacture prototypes and parts, though using different production techniques. We compare these differences in another one of our articles. We'll now consider the benefits and challenges to consider specifically when bringing these machines into an educational setting, as we break down key factors for making a safe learning environment.

2. The Learning Curve

The first thing to consider is the learning curve, both for students and for the educator. If a machine is very complex to learn how to use, then implementing it safely will be more challenging to do. Its important to understand that learning to use a CNC machine typically has two components, the design aspect and the manufacturing aspect.

In this article - "CAD vs CAM, a Beginner's Guide", we compare the differences between CAD and CAM, which dives a bit deeper into this, but in general learning to use a 3D printer is a bit easier than a milling machine, and lasers are somewhere in between. However, that's considering the software side of things only, not the maintenance and setup side of things.

When you choose a machine for your classroom, choose one that has AI-tools and auto calibration like the Carvera and Carvera Air's auto probing and leveling features. Any 3d printer or laser that requires frequent leveling and cleaning puts more strain on the educator who is not only expected to teach, but also maintains their space. When it comes to maintainence, milling machines are often the simplest for upkeep.

Additionally, always ensure you choose a machine that comes with lots of documentations, guides, tutorials, and customer support to help you and your students learn as you get started!

3. Ventilation Requirements

During manufacturing, fumes or dust are often a by-product of production. For 3D printers, these are often fumes created as filament is melted or resin is used. With Laser cutting, smoke and fumes are also a byproduct as materials a burnt and engraved. And for milling, dust is created as a cutting tool machines a piece of material through a subtractive approach.

Some materials are safer to work with than others, like PLA filament compared to ABS filament. Educators should always choose a material that has low VOCs, and ones that are non-toxic. When working with lasers, some materials like PVC would actually emit highly toxic vapors if burnt, and therefore should never be used in the classroom setting.

Some 3D printing and all laser engraving processes require ventilation and exhaust systems, which can be expensive not only to install, but also to maintain as filters need to be cleaned and replaced frequently. Milling processes do not require ventilation like this, only a vacuum to clean up the dust and shavings created. And because there are no fumes exherted during the milling process, mills like the Carvera and Carvera Air can machine virtually any material from woods to plastics, and even metals too.

But dust can be a dangerous hazard as well, especially if inhaled. As such, always choose a milling machine that is fully enclosed and has dust collection systems integrated in order to keep your makerspace clean and worry free.

4. Working Hands-Free

Injuries often happen when you need to handle the machine and parts, so having the ability to manufacture hands-free is a safer approach whenever possible. As mentioned in the previous section, machines that are fully enclosed like the Carvera and Carvera Air are safer for the classroom as students cannot put their hands near the cutting tools or moving parts while the machine is in use. If the lid is opened, the machine will stop immediately.

And if you find yourself needing to clean the work area or handle hot parts, that could be a potential hazard waiting to happen. This is where machines that automatically calibrate and have integrated dust collection will not only make your work environment more autonmous, but safer too. The Carvera's automatic tool changer is a great example of this, completly reducing the need for you to handle sharp bits during the machining process.

5. Eye Protection

Safety glasses should be required when students are in the presence of manufacturing equipment in use. This is often not only for any dust or possible shrapnel, but also for dangerous light rays when working with lasers too. Most lasers will have a cover that shields your eyes from these light rays, but long term exposure is something you want to avoid.

And as already mentioned, machines which are fully enclosed and ones that pause when opened are much safer for students to be around, and often reduce the need for safety glasses in most circumstances.

6. Ear Protection

And the last factor to consider is noise. The need for ear protection is an important one as long exposure to lound noises can cause everlasting damage to a child's hearing. Additionally, it's very difficult to teach over loud noises and distractions too.

3D printers are usually the quietest of all the CNC machines we've discussed thus far, but it's important to note that some 3D printers are significantly quieter than others. Lasers are usually quiet as well, but the exhaust and ventilation systems required for safe operation are typically very loud.

Milling operations can be loud, especially when machining harder materials like metals. And when comparing mills to routers, mills are often much quieter and the better option for a smaller classroom enviornment. But enclosed mills like the Carvera are much quieter than most, and the integrated vacuum is also quieter than another dust collection system you might typically find in a Makerspace too.

Conclusion

Allowing your students to engage with prototyping and production processes is not only very real-world, but also may allow them to bring their ideas to life like they never thought would be possible! There are loads of great CNC machines out there to consider, but ensure you look at the specific features each machine provides for safe operation as you choose the one that best suits your needs.

Look for machines that offer flexibility and training for software requirements, ones that are enclosed, ones that automatically calibrate, and ones that require little to no maintenance too. All of these factors not only will allow you to make a safer learning environment, but a busy one too!

Check out our Getting Started video series and visit our website to learn more about Makera CNC machines for education.