The Apple MagSafe power connector is long gone from their product line, but that doesn’t mean that magnetic connectors aren’t without their charms. It just takes the right application, and finding one might be easier with these homebrew magnetic connectors.
We’ll admit that the application that [Wesley Lee] found for his magnetic connectors is perhaps a little odd. He’s building something called Linobyte, a hybrid art and electronics project that pays homage to computing history with very high-style, interactive core memory modules. The connectors are for the sense wire that is weaved through the eight toroids on each module, to program it with a single byte. Each connector has a 3D-printed boot that holds a small, gold-plated neodymium magnet with the sense wire soldered to it. A socket holds another magnet to the underside of a PCB. The magnet in the boot sticks to the PCB and makes contact with pads, completing the circuit. We know what you’re thinking: heating a magnet past the Curie point is a great way to ruin it. [Wesley] admits that happens, but it just makes the connection a little weaker, which works for his application. The short video below shows how he puts them together.
Laptop chargers face a hard life. They’re repeatedly plugged and unplugged, coiled up, stuffed into bags, thrown around, and just generally treated fairly poorly. Combine this with fairly lightweight design and it’s not uncommon for a laptop charger to fail after a few years. It’s usually the connector that goes first. Such was the case when I found myself face to face with a failed Macbook charger, and figured it’d be a simple fix. Alas, I was wrong.
Unlike most PC manufacturers, who rely on the humble barrel jack and its readily available variants, Apple liked to use the Magsafe connector on its Macbook line. This connector has many benefits, such as quick release in the event someone trips over the cable, and the fact that it can be plugged in without regard to orientation. However, it’s not the easiest to fix. When the charger began failing, I noticed two symptoms. The first was that the charger would only function if the cable was held just so, in exactly the right orientation. The other, was that even when it would charge, the connector would become very hot. This led me to suspect an intermittent connection was the culprit, and it was quite a poor one at that; the high resistance leading to the heat issue.
It’s at this point with any other charger that you get out your trusty sidecutters, lop the end off, and tap away at Digikey to get a replacement part on the way. With Magsafe? No dice. Replacement parts simply aren’t available — a common problem with proprietary connectors. I endeavoured to fix the problem anyway. I began to strip away the metal shell around the back of the connector with my sidecutters, and eventually an angle grinder. A Dremel would have been the perfect tool for the job, actually, but I persevered regardless. After much consternation, I had the connector peeled back and was able to identify the problem.
So I made an awful, kludgey, “there I fixed it” level repair, and I need to come clean. This is really a case of an ill-advised ground.
My thirteen-year-old daughter asked for help repairing her Macbook charging cable. Macbook chargers really aren’t meant to flex around a lot, and if you’re the kind of person who uses the laptop on, well, the lap, with the charger in, it’s gonna flex. Sooner or later the insulation around the plug housing, where it plugs into the laptop, cracks and the strands of wire can be seen. This type of cable consists of an insulated lead wire surrounded by a stranded ground wire. The problem with this configuration is that the stranded ground also gets flexed until it breaks, one strand at a time, until the cable stops working.
So it was with my daughter’s Macbook cable. I didn’t have the money to buy her a new one, and I figured we could repair the break. We busted out her WLC100 and sat down to get our solder on. She started off working while I supervised, then I took over later on.
We began by using an Xacto to cut away enough insulation to expose about half an inch of the stranded wire. We pulled the wire away from the insulated lead wire and twisted it into a single stranded wire parallel to the lead wire. Grabbing for the iron, we tinned the ground and soldered a length of 22-gauge solid wire to it. The way the ground connects to the plug is by passing through a conductive ring. My idea was to solder the other end of the 22-gauge wire to the metal ring. Here’s where things started to go wrong. This is, by the way, the part where I took over so you can blame me and not my kid.
My daughter was using the WLC100’s default tip. I should have grabbed my own iron, a WES51, or at least swapped in its ninja-sharp tip. The WLC100’s default tip is a big fat wedge and it was too big to put next to the plug, and the conductive ring quickly got covered in melted plastic and I couldn’t solder anything to it. Worse, I had accidentally burned through the insulation protecting the lead wire, and had to cover it in electrical tape.
What now? We were left with not being able to use the cable at all. One option was to wait until the goop had cooled and burnish it clean with a Dremel, then attempt to re-solder using an appropriate tip. However, that sounded like a lot of work. The solid wire was still securely soldered to the ground, so instead of trying to attach it to the cable side of the plug, I could connect it to the computer side, by shoving it into the socket alongside the plug. The business end of the plug has a big silver ground surrounding small gold positive leads, and touching the ground with the wire should work just fine, right?
It did. The computer charged up as happy as you’d like. And yet, I was left with the distinct feeling the solution could have been, I don’t know, cleaner. Certainly, the iFixit route shown here comes out much cleaner by sliding off the housing, clipping the damaged wire, and beginning anew. Clean as this is, it’s just waiting to happen the same way again.
So, brethren and sistren, lay on with brickbats and tell what I did wrong. What approaches have you used to fix cables broken where they meet the plug housing, and how do you improve the situation for the future?
Just a few short years ago, it was possible to find scrapped lithium batteries for free, or at least for very cheap. What most people at the time didn’t realize is that a battery with multiple cells might go bad because only one cell is bad, leaving the others ready for salvaging. Now it’s not a secret anymore, but if you can manage to get your hands on some there’s a lot of options for use. [ijsf] took a step further with this hack, taking a few cells from a Panasonic battery and wrangling them into a MagSafe-capable power bank for a Mac.
The real hack wasn’t scavenging batteries, however, it was getting the MagSafe to signal the computer to use power from the battery bank to run the computer only, and not to use any of that energy for charging the computer’s internal batteries. This is achieved by disabling the center MagSafe pin, which is the computer’s communication line to the power adapter. After that, the battery bank could be programmed to behave properly (a feat in itself for lithium batteries) and the power bank was successfully put into operation.
Not only was this hack a great guide for how to repurpose cells from a “dead” battery, it’s also an unparalleled quick reference for any work that might need a MagSafe connector. Of course, if you’re going to work with these chargers, make sure that you’re using one that isn’t a cheap clone.
[Klakinoumi] wanted to use their Magsafe 1 charger from 2007 with their newer Macbook Pro Retina from 2012 — but it had a Magsafe 2 port. There were a few options on the table (buy an adapter, buy a new charger, cry) but those wouldn’t do. [Klakinoumi] went with the brute force option of grinding a Magsafe 1 charger to fit Magsafe 2.
Based on the existence of passive adapters that allow Magsafe 1 chargers to work with newer laptops, we’d assume that the older chargers are probably electrically similar to the newer models. That said, it’s not our gear and we’d definitely be checking first.
With that out of the way, it’s a simple enough modification — grind away the Magsafe 1’s magnet until it fits into a Magsafe 2 port. It really is that easy. The spring-loaded pins all seem to line up with the newer port’s pads. [Klakinoumi] reports it worked successfully in their tests with 2012, 2014 and 2015 Macbooks but that it should be attempted at your own risk — good advice, as laptops ain’t cheap.
Apple has a reputation in the tech world as being overpriced, and nowhere is that perception more common than in the Hackaday comments. The standard argument, of course, is that for a device with equivalent specs, Apple charges a lot more than its competitors. That argument is not without its flaws, especially when you consider factors other than simple specs like RAM and processor speed, and take into account materials used and build quality. But, as this teardown by [Ken Shirriff] shows, Apple’s attention to detail extends beyond simply machining Macbook bodies out of aluminum.
In his teardown, [Ken Shirriff] thoroughly investigates and describes all of the components and circuitry that go into the ubiquitous Macbook charger. Why does it cost $79? Other than the MagSafe connector, what makes it any better than the charger that came with your Toshiba Satellite in the ’90s? Isn’t it just a transformer to convert AC power to DC?
[Ken Shirriff] answers all of this and more, and you may be surprised by what he found. As it turns out, the Macbook charger isn’t just a transformer in a plastic case with a fancy magnetic connector. There is a lot of high-quality circuitry involved to make the power output as clean and stable as possible, and to avoid potential damage to your Macbook that could be caused by dirty power or voltage spikes. Does it justify the costs, even with so many reported failures? That’s for you to decide, but there is no questioning that Apple put more thought into their chargers than simply converting AC to DC.
I’ve said over and over again that Apple’s MagSafe port is the greatest advancement in laptop tech in the last 15 years. Those charger connectors break, though, so how do you fix it? With Lego, of course (Google translatrix). Use a light-colored 1×4 brick so the LED will shine through.
Lets say you’re just slightly paranoid about the Bad Guys™ getting into your computer with 0-days and roller blades. You’d like to connect this computer to the Internet, but you don’t want to leave it connected all the time. The solution? A timer for an Ethernet switch. It’s actually a better solution than doing the same thing with scripts: there’s a real, physical interface, and if the Bad Guys™ get in when you are connected, they could just enable the network adapter anyway. An extremely niche use case, but that’s 99% of the security hacks we see.
The DaVinci 3D printer is an okay printer if you’re cool with the Gilette model. The filament cartridges are chipped, and the software is proprietary. These problems have been solved, and now you can use a standard RepRap heated bed and glass with the DaVinci. At this point, people are buying the DaVinci just to tear it apart.