Most of the projects here involve some kind of electronic product, and some kind of box for storing them. The same is true for almost all commercial electronic products.
Still, choosing a shell is far from solving the problem. For simple electronic products, it is entirely possible to spend more time to make the housing just right, rather than working on the circuit itself. But in most cases, we need to avoid getting stuck in the exact location of the hardware.
There are many options for your house, and although many people use 3D printers by default, there are usually better options. I have wandered on this issue countless times and hope to share the options I have seen and help you determine which is right for you. Let’s talk about the shell!
Cardboard: Ideal for housing and proofreading PCB layout
You need something fast, dirty, and temporary for proof of concept or short-term projects. Why not use some cardboard placed around you?
In this proof of concept, the LCD, switch, power supply, microcontroller, and battery are all in a cardboard box.
The top of the cardboard has a printout of the printed circuit board layout, some key areas have copper tape, and the SMT components are soldered in place. This rough model is used to verify the physical size and mechanical function within a few minutes.
Used to test the injection molded buttons of different products within the 3D printed parts of the new product under development.
The cardboard is easy to use, and you can quickly insert holes and slots for interfaces and connectors. Draw it, shape it, whatever it takes. Use card stock (such as cereal boxes) for higher quality, finer-sized work. In the world of rapid prototyping, cardboard is an excellent choice for generating rapid iterations to test usability and rough ideas. It also has a thickness similar to a 0.062 inch PCB, allowing you to quickly and easily print your design, paste it on the cardboard, cut it out, and wait for the real ones to arrive by mail.
Plastic food container
When you need to be more sturdy or waterproof, reusable plastic food enclosures, including yogurt containers and Tic Tac packaging, can also do a lot. This high-five mobile disco turtle robot was made under the guidance of a 5-year-old child. The yogurt container is equipped with batteries, speakers, Arduino and all wiring to ensure the safety of sensitive components, enough to deal with this limited life monster.
Find something that roughly matches the size and shape you need, and trim and drill as needed. The utility blade is the only tool needed to make a higher fidelity housing. Carefully heating or using glue can seal and glue the parts together. Unless your goal is kitsch products, you should not expect to make more than a few such products, and their durability is limited, so it is expected that this will only last a little longer than cardboard and be more suitable for humid environments.
If you have molding skills and can shape a piece of material as you wish, clay or oven-baked polymer (Sculpey) may be a good choice. InstaMorph is another tool made of plastic that softens and becomes plastic at low temperatures. It comes in flake and granular form, which can be softened with hot water or air, and then processed by hand until it cools.
Use existing chassis
This option has not received enough attention. Existing enclosures are very suitable for small batch production and bridge the gap between prototype and mass production. Shelly, New age shell, Highland, bud, with Hammond It’s all the places I used to use for injection molding, extrusion, or other prefabrication of enclosures, and can be easily modified to meet your exact needs (no, we won’t get paid for mentioning any of them).
Once you are familiar with their product line, you will begin to recognize their shells in other products. You choose the appropriate size and type of housing, most of which provide some form of CAD (or at least a PDF design drawing with relevant dimensions), and often even suggest PCB outlines. Order one or a few, and you can have everything you need for just a few dollars. When you need to put it into production, you can even provide these companies with any milling drawings or drawings printed on any surface, and they will handle these for you, with only a small set-up fee and each part cost.
There is no shortage of articles about 3D printing, even if there are faster, cheaper, and cleaner options, this seems to be the default choice for people.
If your needs go beyond a box, and you must have some kind of special enclosure to fit a specific shape, or you are trying to make it fast or miniaturized, then 3D printing may work. You will have to eliminate the CAD program of your choice, or find an existing design, which is one of the reasons why this option is not available to many people, and it can be very time-consuming. On the bright side, there are a variety of materials to choose from, some services can 3D print and mail parts to you, and many public libraries even use 3D printers as their service.
If you can use it, laser cutting is also a good choice. Usually these are acrylic or plywood shells, although cardboard also works well, with interlocking or straight edges.There are online generators for simple customizable boxes, such as Maker case with Box.py, You can modify them after downloading to add holes and cuts.
Injection molds are the industry standard for mass production, capable of ejecting plastic parts at an amazing speed and running continuously. They can be designed to precise specifications and can be used anywhere from thousands to millions of parts. The downside is the upfront cost. The cost of a basic mold can be in the thousands of dollars, while a real high-volume hardened steel with slide rails, multiple cavities and cooling lines can cost millions of dollars. We have covered injection molding in detail, but the main thing to remember about injection molding is that it is not a one-off, and once the tool is cut, you will not be able to easily change your design.
Other: CNC, casting and composite materials
There are countless other options. You can use CNC to make the housing out of wood or metal in the shop. There are various casting techniques, including 3D printing a mold and casting in the mold, or 3D printing a positive film, creating its silicone mold, and then casting the part in the mold. You can put everything in a temporary enclosure and pour it in (basically pour epoxy in and fill it up). You can use a variety of methods to make different parts of the housing, and even sub-components. I have used 3D printing and laser cutting brackets in existing enclosures.
Before you directly use CAD software to design a box and 3D print it for a few hours, consider other options that may be faster, cheaper, or look better. Of course, this article is not an exhaustive list, but if I missed something important, please mention it below.