Most of us using desktop computers, and plenty of us on laptops, have some sort of fan or pump installed in our computer to remove heat and keep our machines running at the most optimum temperature. That’s generally a good thing for performance, but comes with a noise pollution cost. It’s possible to build fanless computers, though, which are passively cooled by using larger heat sinks with greater thermal mass, or by building more efficient computers, or both. But sometimes even fanless designs can benefit from some forced air, so [Sasa] built this system for cooling fanless systems with fans.

The main advantage of a system like this is that the fans on an otherwise fanless system remain off when not absolutely necessary, keeping ambient noise levels to a minimum. [Sasa] does have a few computers with fans, and this system helps there as well. Each fan module is WiFi-enabled, allowing for control of each fan on the system to be set up and controlled from a web page. It also can control 5V and 12V fans automatically with no user input, and can run from any USB power source, so it’s not necessary to find a USB-PD-compatible source just to run a small fan.

Like his previous project, this version is built to easily integrate with scripting and other third-party software, making it fairly straightforward to configure in a home automation setup or with any other system that is monitoring a temperature. It doesn’t have to be limited to a computer, either; [Sasa] runs one inside a server cabinet that monitors the ambient temperature in the cabinet, but it could be put to use anywhere else a fan is needed. Perhaps even a hydroponic setup.

The cloud is supposed to make everything better. You can control things remotely, with the aid of a benevolent corporation and their totally friendly servers. However, you might not like those servers, and you might prefer to take personal control of your hardware. If that’s the case, you might like to follow the story of [ouaibe] and their quest to free a fan from the cloud.

The unit in question was a tower fan from Dreo. [ouaibe] noted that there was already a project to control the fans using Home Assistant, but pure lower-level local control was the real goal here. Work began on pulling apart the Dreo Android app to determine how it talked to the fan, eventually turning up a webserver on board, but little progress. The next step was to disassemble the unit entirely. That turned up multiple PCBs inside, with one obviously for wireless communication and another hosting a Sino Wealth microcontroller. Dumping firmwares followed,  along with reverse engineering the webserver, and finally establishing a custom ESPHome integration to fully control the fan.

[ouaibe] has shared instructions on how to cut your own fan from the cloud, though notes that the work won’t be extended to other Dreo products any time soon. In any case, it’s a great example of just how much work it can take to fully understand and control an IoT device that’s tethered to a commercial cloud server. It’s not always easy, but it can be done!

[Anthony Kouttron] wanted a fume extractor for his personal electronics lab, but he didn’t like the look of the cheap off-the-shelf units that he found. Ultimately, he figured it couldn’t be that hard to build own portable fume extractor instead.

The build is based around a mighty 110-watt centrifugal fan from an IBM server that’s rated at approximately 500 CFM. It’s a hefty unit, and it should be, given that it retails at over $200 on DigiKey. [Anthony] paired this fan with off-the-shelf HEPA and activated carbon filters. These are readily available from a variety of retailers. He didn’t want to DIY that part of the build, as the filter selection is critical to ensuring the unit actually captures the bad stuff in the air. He ended up building a custom power supply for the 12-volt fan, allowing it to run from common drill batteries for practicality’s sake.

Few of us have need for such a beefy fume extractor on the regular. Indeed, many hobbyists choose to ignore the risk from soldering or 3D printing fumes. Still, for those that want a beefy fume extractor they can build themselves, it might be worth looking over [Anthony]’s initial work.

We’ve seen some other great DIY fume extractors before, too. Even those that use drill batteries! If you’ve been cooking up your own solution, don’t hesitate to drop us a line!

Street sledding, a popular pastime in Norway, is an activity that is slowly dwindling in popularity, at least as far as [Justin] aka [Garage Avenger] has noticed. It used to be a fun way of getting around frozen lakes and roads during winter, and while some still have their sleds [Justin] wanted to see if there was a way to revitalize one of these sleds for the modern era. He’s equipped this one with powerful electric turbines than can quickly push the sled and a few passengers around the ice.

Since this particular sled is sized for child-sized passengers, fuel-burning jet engines have been omitted and replaced with electric motors that can spin their turbine blades at an impressive 80,000 rpm. The antique sled first needed to be refurbished, including removing the rust from the runners and reconditioning the wood. With a sturdy base ready to go, the sled gets a set of 3D printed cowlings for the turbines, a thumb throttle on the upgraded handlebars, and a big battery with an Arduino to bring it all together.

With everything assembled and a sheet of ice to try it out on, the powerful sled easily gets its passengers up to the 20-30 kph range depending on passenger weight and size. There’s a brake built on an old ice skate for emergency stops, and the sled was a huge hit for everyone at the skating pond. There are plenty of other ways to spruce up old sleds, too, like this one which adds a suspension for rocketing down unplowed roads.

Ventilation fans are useful for clearing stuffy or stale air out of a space. However, they also tend to act as a gaping hole into said space. In the case of caravans and RVs, an open ventilation fan can be terrible for keeping the interior  space warm, quiet, and free from dust. “Blast doors” or fan blocks are a common way to solve this problem. [Raphtronic] whipped up a duly-equipped ventilation fan to do just that.

The solution was to create a fan setup with a custom fan holder and a sliding door to block airflow when necessary. [Raphtronic] designed a fan frame for this purpose using parts 3D printed in ASA plastic. This material was chosen such that they could readily withstand the 50 C (120 F) temperatures typical in his Ford Transit camper during the summer. A simple 12 V ventilation fan was then fitted to the frame, along with a sliding door controlled by a 12 V linear actuator.

The mode of operation is simple. A DPDT switch controls the linear actuator. Flipped one way, the linear actuator is fed 12 V in such a polarity as to move it to open the fan door. In this mode, 12 volts is also supplied to the fan to start ventilation. When the switch is flipped the other way, the actuator moves to the closed position, and a diode in the circuit stops the fan spinning backwards. As a bonus, limit switches are built into the linear actuator, so there’s no need for any microcontrollers, “off” switch positions, or additional wiring.

It’s a tidy solution to the problem of ventilating a camper in a clean and effective manner. Files are on GitHub for those wishing to build their own. We’ve seen some great work in this area before, like this off-grid van project that made excellent use of 3D scanning during the build process. If you’ve designed and built your own nifty camping gear, don’t hesitate to drop us a line!

For better or worse, most drivers for PC-related hardware like RGB components and fan controllers are built for Windows and aren’t generally of the highest quality. They’re often proprietary and clunky, and even if they aren’t a total mess they generally won’t work on Linux machines at all, or even on a headless setup regardless of OS. This custom fan controller, on the other hand, eschews the operating system almost entirely in favor of an open source fan controller board that can be reached over a network instead.

The project’s creator, [Sasa Karanovic], experimented with fan splitters to solve his problems, but found that these wouldn’t be the ideal solution given the sheer number of fans he wanted in his various computers, especially in his network-attached storage machine. For that one he wanted ten fans, with control over them in custom groups that would behave in certain ways depending on what the computer was doing. His solution uses two EMC2305 five-fan controller chip which communicates over I2C on a custom PCB with a RP2040 at the center. This allows the hardware to communicate with USB to the host computer for updating firmware and controlling over the network. There’s also a 1-wire and I2C bus exposed in case any external sensors need to be integrated into this system as well. To get power for all of those fans, the board uses a SATA connector to get power from the computer’s power supply.

With the PCB built and all of the connections to the host computer made, the custom board is able to control up to 10 fans in any custom configuration without needing a monitor or a driver since it is accessible over the network through an API. It’s also open-source so any changes to the firmware or hardware can easily be made for most air-cooled PC situations. If you’re less concerned about the internal case temperature and more concerned about all the heat your PC is dumping into a living space, you might want to look into venting your PC outside instead.

If you solder (and we know you do), you absolutely need ventilation, even for that lead-free stuff. Fortunately, [tinyboatproductions] has gotten into air quality lately and is here to help you with their snappy 3D printed air-filtering design.

At the heart of this build is a 120 mm notoriously-quiet Noctua fan coupled with a carbon filter. It does what you’d think — position the fan the right way and it sucks the air through the filter, which catches all those nasty particles.

The only problem is that the Noctua uses PWM, so there’s no governing it with a just potentiometer. To get around this, [tinyboatproductions] introduced an Arduino Nano and a buck converter, both of which were admittedly a bit overkill. Now the speed can be controlled with a pot.

Once control of the fan was sorted, [tinyboatproductions] decide to add an OLED display to show the fan speed and power condition, which is a nice touch. Be sure to check out the build video after the break.

If this doesn’t have quite enough features for you, here’s one that’s battery powered.