Using 3D Printers in the Classroom: Things to Know
Curtis Satterfield, Ph.D.
As educators we often are told of new teaching methods and instructional supplies for use in the classroom. In the past several years the concept of using 3D printing in the classroom has been gaining traction. In this article we will look at ways that you can use a 3D printer in your classroom.
3D Printers can be used in a variety of ways to engage students and enhance the learning environment. The best items to print in your classroom match current areas of your curriculum allowing students to demonstrate their knowledge of the topic.
While 3D printing is exciting and can be a great learning tool for students there are several considerations to make. If you don’t have a 3D printer you need to research and choose the right printer. Then you must find meaningful ways to work it into your curriculum. You’ll need to plan for failures, printer down time, and maintenance. We’ll cover all these issues later in the article.
This article is designed to give you ideas for use of 3D printing in your classroom. It is meant as a guide to help you think of ways to incorporate the technology into your curriculum. The ideas presented are general and not age or grade specific. If you are considering a 3D printer for your classroom my goal is for you to take inspiration from the examples presented and decide if 3D printing is something that will benefit your classroom.
Integrating 3D Printing into your Curriculum
The big question from most educators about 3D printers is “what value does it add to my curriculum?” A 3D printer can help you produce physical objects that help immerse the students in the subjects they are learning about. There are numerous studies that demonstrate hands-on learning is effective at helping students understand and retain what they are being taught. Bringing items to life such as dinosaur skeletons, topographical maps, geometric shapes, and items designed by the students are all examples of 3D Printer usage.
Here are more ideas for implementing 3D printing into your curriculum:
- Have your students find problems in the world that need fixing and print a solution. For example, maybe there is a wobbly desk or chair in your classroom. Have your students design and print a part to fix the problem.
- Let your students imagine a new product and have them print prototypes. Then have them pitch their ideas to their classmates.
- Ask other teachers in the school if there are any educational props they could use. Then ask your students to design and print the needed objects.
- Use specific architecture features to design buildings or community areas.
- If you are teaching biology you could have students print models of cells.
- Think globally. Have students consider problems in the real world and then design and print a solution to the problem.
Before a student can begin designing and printing, they will need to learn about the subject matter at hand. A student cannot design and print a cell if they don’t know anything about the cell. Reread the above list and think about the core content that a student would need to have before the design phase begins. Think about other areas of your curriculum and determine if there are more areas that you can incorporate 3D printing.
You may want to put students in groups for your printing projects. If you only have one 3D printer and lots of students, it will take a long time for each student to print their own projects. Grouping the students and having them vote on a design or allowing each of them to contribute to a design will reduce the number of prints needed. Learning to design and work in a group can be a fun and exciting challenge for students.
There are lots of opportunities to incorporate 3D printing into a curriculum. The examples presented here are meant to provide ideas for how you might utilize 3D printing in your classroom. There are several other considerations about 3D printing in your curriculum that we will discuss in the next few sections.
Choosing a 3D Printer for Your Classroom
If you will be part of the purchasing process for the 3D printer(s) there are a few things to keep in mind. 3D printers will create noise and smells that may be a distraction to students. You can read my articles about how loud 3D printers can be and what 3D printing smells like. To reduce the noise and smell from the printer you can either purchase an enclosed printer or purchase an enclosure for an open printer. Open printers can also be dangerous for classrooms with younger students as the moving parts are exposed. Keep these things in mind when looking for a printer.
A good example of an enclosed printer is the Ultimaker 2+. The print bed and all the working components are enclosed inside the metal and acrylic of the frame. The enclosure reduces the smells and noise that can generate from the printer. The enclosure also offers protection as the heated build plate and hot end are not exposed. This reduces the change of someone touching the moving parts while it’s running. An enclosed printer can also offer better build quality as the print will cool evenly and will not be subject to sudden changes in temperature.
You will also want to purchase printers with good reliability and quality out of the box. If you have the time and are mechanically inclined, you can certainly purchase a less expensive model and spend the time to upgrade and calibrate the printer. If you are looking to start printing great prints right away, you will need to invest in a quality printer. The drawback to enclosed printers is the price. These printers are typically much more expensive than an open printer. However, in a classroom environment, especially with younger students, I recommend an enclosed printer.
Choosing 3D Printer Filament
There are many kinds of 3D filament on the market all with different physical properties. Here is a list of the more popular filaments and their properties. The list below is included for reference to give you an idea of the materials available. I highly recommend using PLA in the classroom.
ABS – Acrylonitrile Butadiene Styrene is a common filament type known for being tough and impact resistant. ABS should be printed in an enclosure and gives off a burning plastic smell when printed. I do not recommend using ABS in a classroom environment.
PLA – Polylactic Acid is one of the favorite filaments of the 3D printing community. It is a biodegradable thermoplastic derived from renewable sources such as cornstarch, sugar cane, and potato starch. PLA requires a much lower nozzle temperature than ABS printing between 180°C and 220°C. PLA is a great choice for classroom printing due to its cost and ease of use.
PET – Polyethylene Terephthalate is often used for mechanical parts that require flexibility and impact resistance. PET offers more flexibility than ABS while maintaining strength. PETG is printed at temperature like ABS between 220°C and 250°C.
PETG – Glycol modified Polyethylene Terephthalate (PETG) is a variant of PET filament that increases the materials durability and impact resistance. Unlike PET this material will not readily absorb water. PETG is also considered food save and can be used for cups, plates, and food containers.
PETT – PolyEthylene coTrimethylene Terephthalate (PETT) is another modified version of PET. PETT is considered food safe and is approved by the FDA.
Nylon – Polyamide filament is a synthetic polymer typically used in industrial applications. Nylon is strong, durable, and flexible. Printed between 220°C – 250°C nylon is perfect for industrial parts such as gears, bearings, and mechanical components. The downside to nylon is that it emits toxic fumes when printing. This is important to know as nylon does not produce and odor when it prints but it is toxic and should be used in a well-ventilated area. I absolutely recommend you not use nylon for printing in the classroom!
Wood filament is made with recycled wood and polymer binding. It is typically used for more decorative applications as it is one of the weaker printing materials. While wood filament looks cool it does give off the smell of burning wood and may irritate students.
Planning for 3D Print Times
We have become accustomed to fast printing from our inkjet and laser printers. Seldom do we need to wait more than a few minutes to print handouts or worksheets. 3D printers are an entirely different matter. Prints can take anywhere from a few minutes to well over 40 hours. The larger your print the longer it will take. It is important to factor length of print time into your curriculum plans.
For example, I printed this Samurai mask on one of my printers. According to the slicer the print time was 20 hours and 52 minutes. The actual print time was 36 hours. This is an extreme example where the details of the model required the printer to move much slower than the slicer expected.
Another consideration for print time is a print with multiple parts. I love the T-Rex skeleton created by Makerbot which you can find here on Thingiverse. I have printed the full T-Rex skeleton twice and it took approximately 40 hours total print time each time. The print time only includes the time the printer was printing parts. It does not account for failed parts, removal of the parts, or preparation for the next print. If you want to print the T-Rex Skeleton I recommend this remix by icefox1983 which includes several improvements to the original model offering better print quality.
These examples are included to show that large parts, while excellent teaching resources, take a long time to print. If you’re covering the Cretaceous Period tomorrow, don’t expect to print out a dinosaur skeleton overnight.
A simple way to roughly estimate the print time is with the slicing software. No matter which slicer you use they will all give you an estimate of print time. The time is only an estimate and will usually take longer to print than the slicer indicates. I’ve found that adding about 30% to the time indicated usually works. The prints will not always take 30% longer but it gives you plenty of padding in your time planning.
The problem with a slicer’s time is that it doesn’t consider the firmware settings of the printer. Certain settings such as acceleration can dramatically increase the print time needed. After using the printer for a while, you will get an idea for how long a print will take as compared to the slicer estimated time.
You also need to factor in time removing prints from the printer and preparing for the next print. If you are using a printer with a heated bed you will want to wait until the bed has cooled down before removing your print. As the heat dissipates the print will come off the bed with very little force. Trying to force the print off the bed prior to cooling can damage both the print and the bed. Cool down time depends on the bed material used in your printer. I have found that using a glass bed cool down can take around 20-30 minutes.
If you are planning to change filaments in between prints be sure to allow yourself extra time. If you are changing material type or color, you will need to extrude the new filament through the nozzle to clean out the old filament.
Plan for Failed Prints
No matter how good a printer is you will inevitably have a failed print. It is important to accept this fact up front and to let your students know there is always a chance their print will fail. When you do have a failed print use this time to engage your students in troubleshooting. Have them research ways to avoid the problem that caused the print to fail. You and your students may not know what caused the failure. Take the time to research possible reasons with them. Troubleshooting is an important life skill and failed prints are great teachable moments.
Logistically you will need to always factor in extra print time for those prints that fail. For example, if you have 10 prints to do and each print will take 15 minutes don’t plan on being done in 2.5 hours. If a print fails, you will need to reprint it and possibly spend time troubleshooting the failure or even performing printer maintenance and repair.
Plan for printer down time
Inevitably something will go wrong with your printer when you least expect it. If your nozzle becomes clogged, you will need to remove the hot end in order to clean it out. If the nozzle clogs at the beginning of class time where you planned to use the printer you will need to change your plans. Other parts on the printer might break and the printer will not be usable until the replacement parts arrive and get installed.
Always have a back up or alternate lesson plan when using 3D printers. Inevitably a print will fail, or the printer won’t work when you need it to. Having a back up plan you can easily transition into another activity and deal with the printer situation later.
Plan for Printer Maintenance
3D printers require maintenance like any other machine. Properly caring for your printer will extend its life span and will lower the chances of printer failure. Depending on your grade level and trust in your students you may try allowing your students to perform maintenance on your printer. Simple tasks such as cleaning out any debris, checking that the belts are tight, and possibly lubricating bearings are great tasks for students.
Budget for Consumables
In addition to filament there are other items on 3D printers that are consumable. If you are not using a heated bed you will need to use a PEI sheet or painters’ tape for bed adhesion. PEI sheets last a long time but eventually will need to be replaced. Painters tape can last several prints with care but will need to be replaced frequently.
Over time the nozzle in your printer will slowly wear out and will need to be replaced. Luckily, nozzles are a low-cost item and last for a long time. If you are printing with specialty filaments like glow in the dark your nozzle will wear out much more quickly. If you plan to print with filaments other than PLA, I recommend getting a steel nozzle as they will last longer.
Conclusion
This article was intended to share information about 3D printers and their possible uses in the classroom. I hope that you were able to gain understanding and inspiration of 3D printer projects that can be incorporated into your classroom. I hope that the information provided here has helped you decide if 3D printing is right for you and your curriculum.