Hello and welcome to part one of The Andrew’s Brain Blog 3D Printing Guide. For the first part of this guide we’ll discuss what 3D printing can be used for and how 3D printers work.
3D printers can be used for creating useful items like replacement battery covers on xbox contollers , potato chip bag clips and even caulking tools. Or it can be used to create completely aesthetic items like an Ultra Swole Pikachu, Christmas ornaments or puppy figures.
Really the only limits are your imagination, creativity, and printer ability. But before getting too far ahead of ourselves, it’s important to understand how 3D printers work before you begin thinking of all your DIY projects.
A very simple and highly recommended beginner 3D printer would be one from the Creality Ender series of printers. The one I currently have, and started 3D printing on, is the Creality Ender 3. In order to explain how most 3D printers work, I will use this printer as a base example.
The Ender 3 is only $209 which is a fair price compared to some other printers out there. In order to keep the price low, they went with a very basic T-Slot Design. The T-Slot design is how many hobbyists used to make home made 3D printers. Essentially you buy some t-slot bars and create the basic structure needed for a 3D printer. It seems dumb, but sometimes the simpler the better. It looks something like this:
The benefit of this design is it’s amazingly simple, very customizable and very affordable. It’s great for understanding the concept of how a 3D printer works because you can see all the moving parts in action. Since there are many owners of the Ender series printers, there are a lot of designs available online to upgrade your printer. Yes… You can 3D print upgrade parts for your 3D printer. If you really wanted to you could 3D print a 3D printer and have yourself a 4D inception printer.
The downside of this design is it’s prone to issues that may need some attention. There may be times where you find yourself leveling your print bed more often than you’d like or you may have the occasional clog in your nozzle that requires a nozzle replacement and that’s not all the problems that may occur. That being said, this is one of the most affordable printers available, which means there are many owners of this printer online who document their common issues and how to address them. So there is a lot of help online for any printing issues related to this printer.
I will go into more depth of the pros and cons of various printers in a later edition of the ABB 3D Printing Guide for those looking to buy their own.
Now that you have a basic understanding of the names for the components on the ender 3 printer, lets get into how it works!
It all starts with the plastic spool. The thin plastic string is loaded into the extruder. The extruder’s function is to bite onto this plastic string and feed it into the teflon tube, which then guides the plastic towards the hot end.
The hot end is made up of a couple parts. It’s obviously got the teflon tube as I’ve mentioned. It’s got a pneumatic coupler, which keeps the tube in place. There’s a heat sink, which prevents heat creep, which is the term used for heat traveling up the hot end and melting the plastic just enough for it to become soft, but not molten. Heat creep will cause the plastic to melt in an undesirable part of the hot end, which leads to clogging. The heat sink will absorb the heat and distribute the heat away from this location. Then we have the heat block, which is a metal block used to heat the nozzle. This block gets extremely hot so please be careful going near it when it is heated. Then we have the nozzle, which can have different hole sizes to have higher or lower quality prints, a few fans to help control the temperature and a thermistor used to give the computer feedback of the current hot end temperature.
Now is where the magic happens. There are a total of 4 motors used for this particular printer (some printers have more motors used for making certain things more robust or stable). We have the x-axis, y-axis, z-axis and extrusion motors. Each of these motors needs to move with precise timing to draw your 3D model properly. The mini computer will execute a series of commands to move the motors to meet these timing constraints. The 3D printing standard for these motor commands is known as G-code. G-code is the output of a tool known as a slicing tool. A slicing tool is a software tool that will take a 3D model (usually in an STL file format) and convert the design into just motor and extrusion commands (along with temperature settings and other printer related settings). Simply a slicer will take your model and converts it into instructions for the printer to follow.
Another important thing to remember is that the printer will complete the 3D model one layer at a time. Starting from the bottom working it’s way up. When the plastic gets to the nozzle and is melted into molten plastic, it will drip onto the heated bed. This means that when plastic leaves the nozzle it’s essentially in a liquid state until it rapidly cools from the air around it. There needs to be a surface directly under the nozzle in order for the plastic to be in the correct location in the xyz coordinate system. When you’re printing a 3D model you will often need support material for any parts of the model that are suspended in air. Support material is a low density structure used to support the parts of your model that are hanging at an extreme angle, usually greater than around 60 degrees from normal.
Now you should have a basic understanding of how a 3D printer works. Different printers may have other features not discussed here, but the basics are all covered. For example some 3D printers have dual extrusion, which means you have two nozzles, two extruders and two hot ends. This gives you the ability to 3D print in 2 different plastics. Usually this is used to 3D print models in two different colors or for printing in two different materials. One material which can be disintegrated in an acid bath which is used for the support and the other a material which will not disintegrate for the actual print. There are even some printers with 3 nozzles attempting to be full color printers by combining the colors of three spools together. But at the core of it all, you still need plastic, an extruder and a hot end. The concept doesn’t change much.
Coming next time in part 2:
- 3D Modeling Software, Slicers, and various printer settings
- Printing Materials
- 3D Printer Comparisons
Thanks for taking the time to read this article! If you have any questions please leave a comment below or feel free to DM me on instagram @andrew_alves8