Naturally, if you want to 3D print a part, you have to have a 3D model of that part. 3D models are created using 3D modeling software, such as CAD (computer-aided design) software. Here are some examples of popular 3D modeling programs:

• Fusion 360 (free for non-commercial use CAD)

• SolidWorks (paid CAD)

• Blender (free surface and organic modeler)

However, most 3D printing beginners don’t have the skills required to use such software. If that’s the case, don’t worry, because there are other solutions.

For starters, there are simpler CAD software options, such as Tinkercad, a program that almost anyone can use without any prior experience. It’s an online app designed by Autodesk, one of the industry’s leading CAD software creators.

With so many people gaining access to 3D printers in recent years, numerous sites have emerged as repositories for 3D models. Here are some of the most popular ones:

• Thingiverse (all free)

• Cults (free and paid)

• Printables (all free)

• MyMiniFactory (many free and some paid)

• CGTrader (few free and most paid)

This way, anyone can get their hands on a model – no modeling skills required!

Once a model is finished in 3D design software, it still needs to be prepared using a special kind of software that translates the model into the script of machine instructions we mentioned earlier. This is done using slicing software, also referred to as a slicer. After importing your 3D model to the slicer, you can adjust the settings to meet your requirements. You can use the slicer to set many important parameters, such as printing speed and temperature, wall thickness, infill percentage, layer height, and many others.

The resulting file consists of G-code, the “language” of 3D printers and CNC machines. G-code is essentially a long list of instructions that the 3D printer will follow to build your model. In other words, 3D printing is impossible without G-code files!

Speed is our third powerful slicer setting. As the name indicates, we’re referring to the speed at which your printhead moves. When spoken of generally, “speed” encompasses many different settings, not just the default movement speed. For example, it can be useful to adjust specific speeds derived from the default value, such as the infill speed, wall speed, and so on.

Usually, it’s good to leave specific speed settings alone and only adjust the default speed if needed. In most slicers, a particular speed will be chosen based on your chosen layer height and material, so it is not necessary to adjust it.

On the other hand, sometimes it’s a good idea to reduce speed when you run into print quality issues. Slow speeds make it much easier to identify which setting is causing problems (if it’s something other than speed).

Retraction is usually the first setting people think about when they see strings, hairs, or whisps on their print. Retraction determines how much and how fast filament is pulled back into the nozzle to prevent material from oozing out when it’s not being extruded. Retraction is controlled by a few specific settings, chief among them being retraction distance and retraction speed.

These settings should be adjusted when you see stringing, but be mindful that retraction isn’t the only solution to this problem and nozzle temperature also plays a role. You should change your retraction settings in small intervals and don’t make any significant increases until you’ve tried lowering the temperature. Too much retraction can cause nozzle jams, as the filament is more aggressively pushed in and out of the nozzle.

An adhesion assistant is an auto-generated physical feature that, when added to a print, should improve bed adhesion. Bed adhesion is how well a part sticks to the build surface, and it’s typically most important for the first layer. There are three main types of adhesion assistant:

• A skirt is a distant and detached perimeter that outlines a print. Skirts don’t provide direct adhesion assistance for a model, but they can get material flowing through the nozzle smoothly before starting the critical first layer. They can also be useful for making last-minute manual adjustments for bed leveling. By default, many slicers will automatically generate a skirt for every print.

• A brim is extra filament, extruded as a set of concentric rings that emanate from a print’s first layer. If your print were a cylinder, the brim would literally look like the brim of a top hat. As far as adhesion assistants go, this is the first step to take if a model is having bed adhesion issues. A brim might help with a print that has a small “footprint”, that is, low surface area contact to the bed, which can greatly reduce adhesion.

• A raft is like an entire part on its own, upon which your model is built. When printing rafts, slicers generally attempt to save material by putting space between adjacent lines. This is the no-holds-barred approach to bed adhesion because the bottom surface area is printed and extended, and your print is actually printed on top of this material. This means that your print never has to touch the surface. Rafts can be useful if warping is an issue.

As you might expect, a skirt takes up the least amount of material and print time, followed by the brim, and then the raft.

Supports are another significant slicer setting and, like adhesion assistants, are slicer-generated. Supports are structures that hold up overhanging features on models if they meet certain requirements, which can be set in your slicer.

These requirements include the overhang angle and the minimum support area. The former determines the minimum angle an overhang has to be before the slicer creates a support to hold it up. The latter governs the minimum area (in mm2) that a support structure has to have to be included in a print.

Other support settings and options are also very important. For example, part orientation plays a key role in how support structures are generated. Other support settings include print speed, support infill density, and more. You shouldn’t change these settings at all if your model doesn’t require supports in the first place, but when necessary, you can tweak them to find a balance between sufficient support and minimum material consumed.

Next up is cooling, which determines the speed of the fans on your printer. While a printer may have numerous fans, such as around your printer’s mainboard, power supply unit, and hot end, “cooling” in this context usually just refers to the speed of your part-cooling fan. Fan speed can typically be set and adjusted as a percentage of total power.

When adjusting the speed of your part-cooling fan, consider the material you’re currently printing with. For example, PLA requires moderate cooling from the part-cooling fan, but ABS shouldn’t have any (because cooling can lead to cracking). If your model has overhangs and you don’t want to use supports, you can try increasing cooling to more rapidly solidify printed overhangs.

In general, it’s impractical to print solid pieces. Solid pieces use a lot of material and can take a long time, and usually the benefit of added strength just isn’t worth it. As opposed to other manufacturing methods, 3D printing is able to benefit from infill, which is the internal filling in 3D printed parts. Infill gives you more control over the strength, weight, material consumption, and internal structure of a part without having to adjust its appearance or external features. In a slicer, infill can be controlled by defining an infill density, set as a percentage, and infill pattern, which is the infill’s structure or form.

More robust infill patterns and larger infill densities will increase printing times and consume more material, but also increase a part’s strength and weight. There are many infill patterns to choose from, all with their own design and characteristics, such as concentric (for flexible parts), cubic (to add strength), gyroid (for parts equally strong in multiple directions) and lines (for the fastest print time). You can set your infill density with a specific pattern to achieve your desired mix of printing strength, material consumption, and printing time.

Shell (or perimeter) thickness represents the number of lines in the walls of your prints, whether they’re at the sides, on the top, or on the bottom. If infill is the “inside” of a print, shells are the “outside”, which means they are completely solid and printed concentrically. Shell thickness is usually set as a value in millimeters or as a number of layers for the walls and the top and bottom layers.

Shell thickness is an important setting to tune because it can significantly impact the strength of your model. The higher the shell thickness, the stronger parts will be and the longer they will take to print. That’s because the more shells you have, the more completely solid layers or walls your machine has to print.

After slicing a model, a couple of steps need to be taken before a 3D printer is ready to print:

• Loading filament: The extruder needs to be ready to extrude filament before printing begins. The loading process begins by heating the hot end to the filament’s molten temperature and then loading the filament into the heated extruder. The Lab Printers have presents for the most common filaments that can be accessed through the "Preheat" menu.

• Bed leveling: In order for the printer to accurately deposit filament and build the object, the build platform must be level. On the Printers in the Lab, the print bed is already leveled and ready to print, so do not alter the bed leveling settings.

• Print surface cleaning: Before every print, the print surface needs to be cleared of any remains from the last print. Do not clean the bed with chemicals, especially when using PETG. This will cause permanent damage to the print bed sheet.

• Adhesion assistants: If you are printing a large model with sharp corners using PLA, it may be beneficial to apply glue stick to the print bed for better adhesion.

As mentioned, FDM 3D printers use spools of filament as the material for creating parts. These filaments are basically specially-engineered thermoplastics that are capable of being melted and cooled and still maintain their structural integrity. 

One of the best features of FDM 3D printers is that they can work with a variety of filament types. Here are just some of the different types of filament that are used in FDM 3D printing:

• Most commonly, you will find PLA, ABS, and PETG. These tend to be cheaper and relatively easy to work with.

• Some special kinds of filament would be flexible (TPU, TPE), nylon, filled (with wood, metal, etc.), and polycarbonate (PC).

Filaments for FDM are also among the cheapest materials used in the 3D printing world.

Please remove your print on time to allow the next person to print. 

Make sure to wait for the print bed to fully cool down before removing your print. Removing the print before it has fully cooled down might damage the print and the print bed.

Do not use a metal scraper on the removable flexible bed. 

Instead, remove the bed once cool and slightly bend it in and out so that your part breaks free.