With 3D printers growing more affordable by the day, it has become common place to see them begin appearing in not only the home workshop, but inside EE labs everywhere. Even though engineering and 3D printing have been running hand in hand for decades now, the recent incursion of budget friendly 3D printers are leaving many wondering how to incorporate them into their projects workflow.
While I am not an electrical engineer, many of my friends are and I often find myself answering questions about 3D printing and how they can be used by an EE. My usual response is along the lines of: What can’t you do with a 3D printer? I realize this answer does little to answer their question, and I am writing this blog series to answer this question once and for all.
For years, custom enclosures for prototype boards and products have been a very expensive to produce and required machining from metal or plastic, or waiting weeks on a 3D printed model to arrive from a 3D Printing facility. The beauty of having an inexpensive 3D Printer is that you can quickly heat up the unit and in just a few hours, a strong, rigid and accurate case prototype can be in your hands, ready for electronics.
In the video below, you can see my Lulzbot AO-100, a early Mendel Max-based 3D printer costing about $1700 (Current Model is the Lulzbot Taz 3 which cost about $2200,) printing a protective case for one of my Raspberry Pi boards. The beauty of this is that as with many of the popular development boards, designs already exist on popular 3D model sharing sites such as Thingiverse.com. I was able to search and find a suitable case for my Raspberry Pi within just a few minutes, and after a few minutes preparing my printer, I began the printing process. Overall it took just over 2 hours and fit was excellent right out of the box!
While the case may not be as refined as one machined from a block of aluminum or delrin plastic, it gets your Raspberry Pi inside a protective case, and provides an easy way to mount the device to a surface. There are a multitude of pre-designed cases on Thingiverse which range from utilitarian to artistic and even cases designed solely to protect the bottom of the board from stray shorts that could be caused from handling or a wayward screw driver lying on your bench.
3D objects have even been designed to hold such peripherals as the Raspberry Pi Camera module, 4D Systems’ touch-screen add-on boards for the Arduino and Raspberry PI. Custom enclosures can be designed to include a cooling fan to help keep sensitive components from overheating during use, or even to mount daughter boards to the PCB in a stable manner. This can be seen in the image below where a mount was designed to hold the Raspberry Pi Camera Module above the Raspberry Pi itself.
Cases can be found on Thingiverse for nearly every popular development board on the market today, including big names such as Arduino, Beagle Bone Black, Fez Domino, VIA APC, and many more. If a case for your board is not available, building one is quick and as simple as using something like Sketchup and a pair of digital calipers to get measurements. There is are a couple of extra steps required after the design process which include exporting the file to .STL format (through the use of a plugin such as this,) and then running that file through a processing service such as Netfab to condition the file for 3D printing. Conditioning basically involves filling in holes in the model, making everything manifold, and increases the number of triangles in the mesh for a better quality print.
The printer can also be used to create quick mounting points for switches and connectors on larger prototypes your building. One good example is the way Lulzbot incorporated the power switch on its AO-100 and AO-101 3D Printers. In the image below, you can see a custom designed part I created to mount a ultra-sonic ranging sensor to a servo for positioning use on a simple robot chassis. I created this mount using Sketchup in less than 20 minutes using nothing more than a pair of digital calipers.
You will also notice that I included the Sketchup design file in the posting and have opened sourced the design. This is something I urge everyone to do if they are legally allowed to. Growing the online repository of free-to-use, free-to-modify, open-source 3D files will only serve to make the maker and engineering community stronger. At some point in the near future, almost everything you would need to create for your project outside of one-off custom parts will easily be available for download from sites like Thingiverse.
Finally, one of the cooler things I wanted to touch on is the ability to create handy tools for use on your workbench. On Thingiverse, users have uploaded models that allow you to print everything from Oscilloscope probe mounts to very handy items such as custom PCB vices. Customizing your workspace has never been easier, and with just a few ounces of plastic, one can print screw driver organizers, hook up wire spool holders, and even things such as jumper wire combs that help make sense of that tangled mass of breadboard jumper wires.
The point I am hoping to get across is that the practical usefulness of a 3D printer in an electrical engineering workspace is almost limitless, and is only hindered by a lack of outside-the-box thinking. The time, and money saved by prototyping enclosures in house is immense, and the ability to tweak the design and then hold the new revised part in hand in just a couple of hours makes life much easier and less stressful when deadlines are a concern.
Thanks for joining me today. In part two, I will be walking you through the steps necessary to actually build a case for the Beagle Bone Black and maybe one of the new LCD screens it has available. If you have any questions, suggestions, or thoughts on this series, please feel free to send me a message, or leave a comment below.