We’re used to our domestic appliances being completely automated in 2020, but not so long ago they were much simpler affairs. Not everything required a human to run it though, an unexpected piece of electromechanical automation could be found in British bedrooms. This is the story of the Goblin Teasmade, an alarm clock with a little bit extra.
A dead refrigerator is an occurrence determined to frustrate any homeowner. First there’s the discovery of hundreds of dollars in spoiled food, and then the cost of a repair call and the delay of the inevitable wait for parts. It’s clear to see why a hacker like [Mr. Carlson] would seek another way.
Now, normally a fridge repair video would by unlikely fodder for a Hackaday article. After all, there’s generally not much to a fridge, and even with the newer microprocessor-controlled units, diagnosis and repair are usually at the board-level. But [Mr. Carlson] has had this fridge since 2007, and he’s got some history with it. An earlier failure was caused by the incandescent interior lights welding relay contacts closed thanks to huge inrush currents when starting the cold filaments. That left the light on all the time, heating the interior. His fix was a custom solid-state relay using zero-crossing opto-isolators to turn the bulbs on or off only when the AC power was at a minimum.
That repair kept things going for years, but when the latest issue occurred, [Mr. Carlson] took a different tack. He assumed that a board that has been powered 24-7 for the last twelve years is likely to have a bad capacitor or two. He replaced all the caps, threw in a few new relays to be on the safe side, and powered the fridge back up. It whirred back to life, ready for another decade or so of service.
Kudos to [Mr. Carlson] for his great repair tips and his refusal to surrender. The same thing happened when his solder sucker started to give up the ghost and he fixed it by adding a variable-frequency drive.
Hackers tend to face household problems a little differently than ordinary folk. Where the average person sees a painful repair bill or a replacement appliance, the hacker sees a difficult troubleshooting job and the opportunity to save some cash. [trochilidae] was woken one day by the dreaded Clacking Clanking Scraping Sound, or CCSS, and knew that something had to be done.
[trochilidae] reports that usually, the CCSS is due to the child of the house destroying his lodgings, but in this case, the source was laundry based. The Miele tumble dryer was acting up, and in need of some attention. What follows is a troubleshooting process [AvE] would be proud of – careful disassembly to investigate the source of the problem. Initial efforts found a loose bulb that was unrelated, before landing on a mysterious spring that wouldn’t fit back into place. In the end, that’s because it had no right to be there at all – an underwire had escaped from a bra, before becoming entangled in the dryer’s bearing. With the culprit identified and removed, it was a simple reassembly job with some attention also paid to the condenser and filters to keep things in ship-shape.
It just goes to show – a bad noise, if properly investigated in a prompt manner, doesn’t have to be the end of the world. A bit of investigation goes a long way, and can save you a lot of money and heartache.
We’ve seen appliances giving hackers trouble before – like this aging washing machine that got its mechanical brain replaced with an Arduino.
No matter how mad your 3D printing skills may be, there comes a time when it makes more sense to order a replacement part than print it. For [billchurch], that time was the five-hour window he had to order an OEM part online and have it delivered within two days. The race was on — would he be able to model and print a replacement latch for his dishwasher’s detergent dispenser, or would suffer the ignominy of having to plunk down $30 for a tiny but complicated part?
As you can probably guess, [bill] managed to beat the clock. But getting there wasn’t easy, at least judging by the full write-up on his blog. The culprit responsible for the detergent problem was a small plastic lever whose pivot had worn out. Using a caliper for accurate measurements, [bill] was able to create a model in Fusion 360 in just about two hours. There was no time to fuss with fillets and chamfers; this was a rush job, after all. Still, even adding in the 20 minutes print time in PETG, there was plenty of time to spare. The new part was a tight fit but it seemed to work well on the bench, and a test load of dishes proved a success. Will it last? Maybe not. But when you can print one again in 20 minutes, does it really matter?
Have you got an epic repair that was made possible by 3D printing? We want to know about it. And if you enter it into our Repairs You Can Print Contest, you can actually win some cool prizes to boot. We’ve got multiple categories and not that many entries yet, so your chances are good.
Nespresso is a variant of disposable single serve coffee pods with an extensive, expensive, and proprietary accessory line. After selling inconvenient bits of his soul for convenience and, admittedly, fairly tasty shots of coffee, [Chriss Lott] was predictably betrayed by his Nespresso Jura coffee machine.
Rather than simply exchange more local currency for a replacement revenue guarantee for the Nestle conglomerate, he did what any self-respecting hacker would do and tried to fix it himself. Unfortunately he quickly found their cunningly oval shaped security screws to be more trouble than his time was worth. He listed his remaining coffee pods for free on craigslist and decided to toss the machine in the planned obsolescence receptacle which comes standard in any civilized home.
This is where our story would end were it not for the kindness of a fellow hacker. [Dave H] was browsing through craigslist when he spotted the sad tale. However, possessing a different skillset from [Chris], [Dave] had solved the particular oval shaped conundrum with a security screwdriver hand made from an old bolt. He answered his fellow hacker’s vaguely ardent plea and mailed the converted bolt over to [Chris]’s house.
With the proper tool in hand, [Chris] quickly discovered that all that was standing between him and his convenient coffee was a bit of schmoo between the cost cutting membrane switch and its mating pad on the circuit board. With the practically free repair complete, the machine happily vibrated back to life and produced coffee as if its planned obsolescence wasn’t for another few years. We assume a Nestle engineer was thrown into the pit on principle for this loss (they, of course, are evil enough to have a pit).
We’re not sure how the story proliferated through the internet, but we do know that it was inspirational to many convenient caffeine deprived hackers with similar problems. [Chris] found himself the hub in a network of circumnavigating security screw circumventing hackers.
[Dave]’s hacked bolt was the first to go on an adventure resulting in the repair of many machines before the postmen lost it under a cart, standard procedure. A replacement was purchased from an eBay seller for a hefty $40 american dollars and took up the journey where it left off. Others sent in guides on making the tool for those unwilling to wait for one to be shipped. In fact, even the maker of the $40 dollar tool weighed in on the issue. Apparently he was unaware that the consumer and commercial Nespresso machines used the same tools. A hacker himself, he ran a listing of the custom tool at a quarter of the price for the home repairman and another for the commercial appliance at the higher price.
The whole page is an entertaining read, for a certain kind of person, about appliance repair, reverse engineering, and camaraderie. Happily, the hub is still alive. If you find yourself with an oval screw which needs turning, get in touch with [Chris] and a strange community’s kindness will have a nomadic security bit crossing nations your way soon.
2014 was the year that the Internet of Things (IoT) reached the “Peak of Inflated Expectations” on the Gartner Hype Cycle. By 2015, it had only moved a tiny bit, towards the “Trough of Disillusionment”. We’re going to try to push it over the edge.
Depending on whom you ask, the IoT seems to mean that whatever the thing is, it’s got a tiny computer inside with an Internet connection and is sending or receiving data autonomously. Put a computer in your toaster and hook it up to the Internet! Your thermostat? Hook it up to the Internet!? Yoga mat? Internet! Mattress pad? To the Intertubes!
Snark aside, to get you through the phase of inflated expectations and on down into disillusionment, we’re going to use just one word: “security”. (Are you disillusioned yet? We’re personally bummed out anytime anyone says “security”. It’s a lot like saying “taxes” or “dentist’s appointment”, in that it means that we’re going to have to do something unpleasant but necessary. It’s a reality-laden buzzkill.)
[electronicsNmore] has uploaded a great teardown and tutorial video (YouTube link) about wax motors. Electric wax motors aren’t common in hobby electronics, but they are common in the appliance industry, which means the motors can be often be obtained cheaply or for free from discarded appliances. Non-electric wax motors have been used as automotive coolant thermostats for years. Who knows, this may be just what the doctor ordered for your next project.
As [electronicsNmore] explains, wax motors are rather simple devices. A small block of wax is sealed in a metal container with a movable piston. When heated, the wax expands and pushes the piston out. Once the wax cools, a spring helps to pull the piston back in.
The real trick is creating a motor which will heat up without cooking itself. This is done with a Positive Temperature Coefficient (PTC) thermistor. As the name implies, a PTC thermistor’s resistance increases as it heats up. This is the exact opposite of the Negative Temperature Coefficient (NTC) thermistors we often use as temperature sensors. PTC’s are often found in places like power supplies to limit in rush current, or small heating systems, as we have in our wax motor.
As the PTC heats up, its resistance increases until it stops heating. At the same time, the wax is being warmed, which drives out the piston. As you might expect, wax motors aren’t exactly efficient devices. The motor in [electronicsNmore’s] video runs on 120 volts AC. They do have some advantages over solenoid, though. Wax motors provide smooth, slow operation. Since they are resistive devices, they also don’t require flyback diodes, or create the RF noise that a solenoid would.