Most projects around here involve some sort of electronics, and some sort of box to put them in. The same is true of pretty much all commercially available electronic products as well.
Despite that, selecting an enclosure is far from a solved problem. For simple electronics it’s entirely possible to spend more time getting the case just right than working on the circuit itself. But most of the time we need to avoid getting bogged down in what exactly will house our hardware.
The array of options available for your housing is vast, and while many people default to a 3D printer, there are frequently better choices. I’ve been around the block on this issue countless times and wanted to share the options as I see them, and help you decide which is right for you. Let’s talk about enclosures!
Some ideas are so bad that we just try them anyway, at least that seems to be [Ivan Miranda]’s philosophy. No stranger to just totally ignoring the general consensus on what you can (or at least should) or can’t make with a 3D printer, and just getting on with it, [Ivan] may have gone a little too far this time. Since umbrellas are, well, boring, why not try to keep dry with an air-curtain hat?
As you’ll see from the video, attempting to 3D print an impeller to run from a BLDC motor didn’t exactly go well. The imbalance due to imperfections in the printing process (and lack of an easy way balance it post-print) caused incredibly unpleasant (and possibly damaging) vibrations directly into his skull, not to mention the thing self-disassembling in a short time.
Not to be discouraged, he presses on regardless, substituting an electrical ducted fan (EDF), increasing the silliness-factor oh-so-little, after all as he says “I think I have a solution for all the issues — more power!”
EDFs and other kinds of ducted fans are used in many applications nowadays. Thanks to advances in rare-earth magnets enabling more powerful brushless motors, combined with cheap and accessible control systems, there has never been a better time to drop an EDF into your latest madcap idea. We have covered many ducted fan projects over the years, including this great video about how ducted fans work, which we think is well worth a watch if you’ve not already done so.
The “rain in spain, stays mainly in the plain” doesn’t actually reflect reality, as most rainfall is actually recorded in the mountainous north, rather than the central ‘plain’, But regardless, it never rains when you want it to, certainly in the Basque country where [Ivan] is based. Initial testing was done with a hose pipe, in the shop, which shows a certain dedication to the task in hand to say the least.
He does demonstrate it appearing to actually work, but we’re pretty sure there is still plenty of room for improvement. Although, maybe it’s safer to just shelve it and move on the next mad-cap idea?
What do you get when you cross a day job as a Medical Histopathologist with an interest in 3D printing and programming? You get a fully-baked Open Source microscope, specifically the Portable Upgradeable Modular Affordable (or PUMA), that’s what. And this is no toy microscope. By combining a sprinkle of off-the-shelf electronics available from pretty much anywhere, a pound or two of filament, and a dash of high quality optical parts, PUMA cooks up quite possibly one of the best open source microscopy experiences we’ve ever tasted.
GitHub user [TadPath] works as a medical pathologist and clearly knows a thing or two about what makes a great instrument, so it is a genuine joy for us to see this tasty project laid out in such a complete fashion. Many a time we’ve looked into an high-profile project, only to find a pile of STL files and some hard to source special parts. But not here. This is deliberately designed to be buildable by practically anyone with access to a 3D printer and an eBay account.
The project is not currently certified for medical diagnostics use, but that is likely only a matter of money and time. The value for education and research (especially in developing nations) cannot really be overstated.
A small selection of the fixed and active aperture choices
The modularity allows a wide range of configurations from simple ambient light illumination, with a single objective, great for using out in the field without electricity, right up to a trinocular setup with TFT-based spatial light modulator enabling advanced methods such as Schlieren phase contrast (which allows visualisation of fluid flow inside a live cell, for example) and a heads-up display for making measurements from the sample. Add into the mix that PUMA is specifically designed to be quickly and easily broken down in the field, that helps busy researchers on the go, out in the sticks.
The GitHub repo has all the details you could need to build your own configuration and appropriate add-ons, everything from CAD files (FreeCAD source, so you can remix it to your heart’s content) and a detailed Bill-of-Materials for sourcing parts.
We covered fluorescence microscopy before, as well as many many other microscope related stories over the years, because quite simply, microscopes are a very important topic. Heck, this humble scribe has a binocular and a trinocular microscope on the bench next to him, and doesn’t even consider that unusual. If you’re hungry for an easily hackable, extendable and cost-effective scope, then this may be just the dish you were looking for.
We’ve always been delighted with the thoughtful and detailed write-ups that accompany each of [Tommy]’s synth products, and the background of his newest instrument, the Scout, is no exception. The Scout is specifically designed to be beginner-friendly, hackable, and uses 3D printed parts and components as much as possible. But there is much more to effectively using 3D printing as a production method than simply churning out parts. Everything needed to be carefully designed and tested, including the 3D printed battery holder, which we happen to think is a great idea.
3D printed battery holder, with spring contacts inserted by hand.
[Tommy] also spends some time explaining how he decided which features and design elements to include and which to leave out, contrasting the Scout with his POLY555 synth. Since the Scout is designed to be affordable and beginner-friendly, too many features can in fact be a drawback. Component costs go up, assembly becomes less straightforward, and more complex parts means additional failure points when 3D printing.
[Tommy] opted to keep the Scout tightly focused, but since it’s entirely open-sourced with a hackable design, adding features is made as easy as can be. [Tommy] designed the PCB in KiCad and used OpenSCAD for everything else. The Scout uses the ATmega328, and can be easily modified using the Arduino IDE.
Many arcade machines can be emulated and handily controlled with the standard joystick and button combos. However, a few don’t feel quite right without some extra equipment, motorcycle racing games being one of them. So, no longer content to go to an arcade to get his fix, [The Q] welded his own motorcycle simulation rig for playing racing games at home.
After an initial design was sketched out, rectangular tube steel was cut to size and welded together with a MIG welder. A central shaft linked to some secured bearings made the central pivot point. A few pistons offered the resistance needed for leaning into the curves. To the central shaft, a seat and an old bicycle fork were attached. A clever linkage from the handlebars to the base causes the bike to tilt when turning the handlebars and vice versa.
The bike was ready for prime time after some grinding, orange paint, a license plate, and some lights and grips. [The Q] just needed to get the angle of the bike into the simulation of their choice. While we expected a teensy or other microcontroller emulating a controller, [The Q] went for a somewhat simpler approach, and 3D printed a cradle to hold a PlayStation controller. Little levers pull strings to articulate the joystick, and a cable from the throttle grip pulls back the trigger on the controller. All in all, the experience looks pretty decent, particularly when you’re comparing it to a motocross arcade machine. What it really needs are some fans blowing for the effect of the air stream coming at you.
The majority of non-SLA resin 3D printers, certainly at the hacker end of the market, are most certainly LCD based. The SLA kind, where a ultraviolet laser is scanner via galvanometers over the build surface, we shall consider no further in this article.
What we’re talking about are the machines that shine a bright ultraviolet light source directly through a (hopefully monochrome) LCD panel with a 2, 4 or even 8k pixel count. The LCD pixels mask off the areas of the resin that do not need to be polymerised, thus forming the layer being processed. This technique is cheap and repeatable, hence its proliferance at this end of the market.
They do suffer from a few drawbacks however. Firstly, optical convergence in the panel causes a degree of smearing at the resin interface, which reduces effective resolution somewhat. The second issue is one of thermal control – the LCD will transmit less than 5% of the incident light, so for a given exposure at the resin, the input light intensity needs to be quite high, and this loss in the LCD results in significant internal heating and a need for active cooling. Finally, the heating in the LCD combined with intense UV radiation degrades the LCD over time, making the LCD itself a consumable item.
A few 3D printers have had a deserved reputation for bursting into flames. Most — but apparently not all — printers these days has firmware that will detect common problems that can lead to a fire hazard. If you program your own firmware, you can check to see if you have the protection on, but what if you have a printer of unknown provenance? [Thomas] shows you how to check for a safe printer. Also check out his video, embedded below.
The idea is to fake the kind of failures that will cause a problem. Primarily, you want to have the heaters turned on while the thermistor isn’t reading correctly. If the thermistor is stuck reading low or is reading ambient, then it is possible to just drive the heating element to get hotter and hotter. This won’t always lead to a fire, but it could lead to noxious fumes.
