3D printing has revolutionized manufacturing by creating structures in minutes that would have taken days if created through traditional means of production and manufacturing. Printed circuit boards are the primary ingredients of electronic products and driving the world towards automation and digitalization. When printed circuit boards (PCBs) are met with 3D printing, it creates a perfect impetus to foster the modern era’s economic and technological growth. Before going into details of how 3D printing and printed circuit board technology will collaborate, let us discuss what does 3D printing really means and what is meant by 3D printed circuit boards.
What is 3D Printing?
3D printing is an additive process of creating three-dimensional solid objects from a digital file. In this process, successive layers of the material are laid down until the object is created. In the early 1980s, 3D printing was considered suitable only for aesthetic prototypes. The technological explosion of the 21st century allows us to use 3D printing as industrial production technology, so 3D printing is used synonymously with additive manufacturing. The antonym of this additive process is the subtractive process in which cutting or hollowing out a piece of metal or plastic with a machine is done.
What does It Mean by 3D Printed Circuit Boards?
We live in a 3D world, but most of our electronic products are in 2D but What if the circuits can be embedded directly into whatever shape we want? That would be awesome because it can save time and can add efficiency to this whole process. Having a custom Printed Circuit Board made can be costly and time-consuming, and you have to put much effort into it to make everything in place. The printed circuit board are small, but the process to make them is lengthy. To lessen the cost, companies in the developed world outsource the production and manufacturing of printed circuit boards to Asian countries. It slows down the whole process. To overcome this difficulty, we need a 3D printer that can efficiently produce 3D printed circuit boards and fast-track the whole process. There are multiple methods to create 3D printed circuit boards, but the two main methods to create 3D printed circuit boards are:
- Using Conductive Filament
- Creating Hollow Traces
We will now discuss these methods in detail.
Using Conductive Filament
You need to split your design into two main parts if you have only access to single extrusion. Multiple layers can also be created, but first, you have to master the double layer mechanism. The steps involved in this process can be summarized as follows:
- Start the process with the modeling of a pattern that should be few layers high. Leave holes for external components to be installed. This model will act as traces printed in the conductive material.
- After modeling a pattern, you will create a base print, and this print will fill in the gaps between and around the circuitry. You can do this by simply subtracting the pattern from the first step from a solid block.
- By aligning the associated coordinates, the two designs from the above two steps should be saved differently. Now, you can slice the models and uploads them to the 3D printer.
- Now, you can load your conductive filament and print the traces.
- Without removing the traces, you will now load your non-conducting filament and print the second model. Now, you have created one solid print from two different materials.
Now that you have your 3D printed circuit board, components are attached in the same way as you do in a normal PCB. In this process, a precaution must be observed that the soldering iron must not come too close to the printed board.
A variety of conductive filaments are available in the market. Most of the conductive variants of filaments such as Acrylonitrile Butadiene Styrene (ABS), Polylactic acid, or Polylactide (PLA), Polystyrene is commonly known as HIPS, or Thermoplastic Polyurethane (TPU), are used in 3D printed circuit boards. Most of these filaments contain Graphene, a kind of semi-conductor, and it allows these filaments to conduct electricity. The conduction of electricity is not as efficient as the metals but still good enough to make an efficient printed circuit board.
Creating Hollow Traces
In this process, we 3D print a model and then this model, and in this model, there are hollow traces. Later, this model is filled with conductive substances. This process involves half the work we have done in the process of conductive filament. The other half goes to the adding of the conductive material. The main steps involved in this process can be summarized as follows:
- Start by modeling a pattern just like the conductive filament process. It should be few layers high and subtract from a solid block. Only empty spaces in which your traces will go should be left. It should be kept in mind that manually adding conductive material is not efficient as a machine. That is why you should design your hollow traces somewhat wider than required.
- A non-conductive filament like PLA, PETG, and ABS should be selected, and the model should be printed.
- The next step is to place your circuit components and use your choice’s conductive material to fill your model gaps. You can use a syringe or pipette for this process.
- Give some time to your conductive material to settle down and dry. Silicon extrusion process can be used to protect the board from oxidization or moisture
Now, let us move on to differentiate between the 3D printed circuit boards and Non-3D printed circuit boards based on the method used in creating PCBs.
Difference between 3D Printing and Non-3D Printing Methods
If you search for 3D printing circuit boards, you may come across many projects that seem like 3D PCBs, but they are not 3D printing projects in reality. For example, drawing a protective mask on board when a pen is attached to the print head is not a type of 3D printing method. It is because an itching liquid is used to remove the untouched areas and create traces. Creating Hollow Traces method is somewhat similar to this process. However, the working principle is not the same, and hence the example mentioned above is not included in the 3D printing methods.
There are two main things in 3D printing on which you can analyze that whether the method falls in the 3D printing category or not:
- You can print a model with traces of conductive filament
- You can create hollow trenches that are later filled in with conductive material.
These two methods are discussed in detail in the first half of the article.
There are various advantages and disadvantages attached to a 3D printed circuit board. First, we will discuss the drawbacks of using 3D printed circuit boards and then move on to the benefits of using 3D printed circuit boards.
Drawbacks of Using 3D Printed Circuit Boards
The drawbacks of using 3D printed circuit boards can be listed as:
- The first drawback is the limited availability of material. 3D PCBs are made by temperature-controlled metals or plastics, and not all metal and plastics can be temperature-controlled.
- The material used in 3D printed circuit boards is not environment friendly, and they cannot be recycled. Also, very few of the metals and plastics used in 3D printing of printed circuit boards are food-safe.
- The print chambers used in the 3D printer have limited size, and the size of these chambers also restricts the output these chambers can produce. It means for a larger project; you need to print different parts separately and then join them together. It will be time-consuming, and manual labor is required, so the cost is increased.
- The post-processing methods influence the speed of obtaining a finished product, especially in big projects. Post-processing methods include water jetting, sanding, air or heat drying, chemical soak and rinse, etc.
- Design is both the strength and disadvantage of 3D printed circuit boards. Some printers have a lower tolerance, and that is why design inaccuracies happen, and final parts may differ from the original design. These design inaccuracies may be corrected in the post-processing methods, but they will increase the cost, as mentioned earlier.
These were some of the drawbacks of 3D printed circuit boards. Now, we will discuss the advantages of using 3D printed circuit boards.
Benefits of Using 3D Printed Circuit Boards
Despite their numerous drawbacks, 3D printed circuit boards are the future. The benefits of using 3D printed circuit boards can be summarized as
- 3D printing allows more complex designs to be completed without much human effort. This flexibility in design is advantageous in smaller projects. The traditional manufacturing process does not offer this luxury.
- 3D printed circuit boards are way cheaper than the traditionally manufactured PCBs. Also, rapid prototyping can be done through 3D printers. For larger projects, you can assemble parts faster than the traditional manufacturing process, and design modifications can be completed at a much more efficient rate.
- A 3D printer has a virtual library where you can store many designs, and any design can be printed on-demand without any prior notice. This print-on-demand option is handy in small and medium enterprises.
- If you want a slight improvement or a change from the previous design you completed through a 3D printer, you can make changes in the STL or CAD file in the virtual library. This will save you time, and you can experiment with different designs too. Also, printed circuit boards’ effectiveness can be gauged quickly, and any revision can be done instantaneously before mass production.
- One of the most important advantages of 3D printed circuit boards is that they are produced without creating any waste. This process saves the resources and the cost of the material being used in creating a printed circuit board.
It is clear from the above discussion that 3D printed circuit boards have their advantages and disadvantages. However, they cannot be ruled out from the race of manufacturing PCBs because they are the future. With technology leaps, it will become the ultimate manufacturing mode replacing the traditional production methods, which require more time and are costlier than the 3D Printed circuit boards. Still, there arises one question that can this production process be fully automated?
Can the Process of creating 3D Printed Circuit Boards be Fully Automated?
Technology has made it possible to use things that were once part of sci-fi movies. With the pace at which technology is growing, it cannot be ruled out that the whole process of 3D printed circuit boards can be fully automated in the near future. However, currently, there are various limitations in full automation of this process, including material tolerance, 3D printer output size, etc. 3D printed circuit boards are only successful in smaller projects in the present era. However, there is a great chance of incorporating 3D printed circuit boards in mass production industries once the technological flaws are overcome.
By concluding this article, I would like to say that 3D printed circuit boards will revolutionize the world in a way maybe similar to that of impact created by the invention of integrated circuits, which subsequently led to the technological revolution. We, human beings, need to invest in this futuristic technology to cover any loopholes present in 3D printed circuit boards’ full automation.