This utilitarian-looking device takes an unusual approach to a problem that many projects face: enclosures. [Jan Mrázek] created a device he calls the Morse Thing for a special night’s event and used what appears to be a humble two-by-four plank for the enclosure. The device is a simple puzzle using Morse code and was intended to be mounted to a railing, so [Jan] milled out the necessary spaces and holes for the LCD and buttons then applied labels directly to the wood via toner transfer – a method commonly used for making PCBs but also useful to create clean, sharp labels.
We’ve done a lot of PCBs with the toner transfer method over the years. The idea is simple: print a pattern using toner (which is just ground up black plastic) and then use an iron or other heat and pressure device to transfer the toner to a copper-clad board. It works and it works well. But getting just the right combination of heat, pressure, release paper, and toner is sometimes tricky.
Some people hack their printers to turn off the fuser wire (to make the toner not stick to the paper) or to run a PCB directly through it. If you have a big expensive laser printer, though, you might not want to chop it up just to run PCBs. Have you looked at laser printer prices lately? We aren’t sure if it is cheap units flooding the market, or the overwhelming popularity of color printers, but you can pick up a Pantum P2500 for about $25 or $30–and probably get WiFi printing at that price. [Mlermen] picked one of these up and shows you how to convert it to a PCB printer.
The “Navigation Thing“ was designed and built by [Jan Mrázek] as part of a night game activity for high school students during week-long seminar. A night-time path through a forest had stations with simple tasks, and the Navigation Thing used GPS, digital compass, a beeper, and a ring of RGB LEDs to provide a bit of “Wow factor” while guiding a group of students from one station to the next. The devices had a clear design direction:
“I wanted to build a device which a participant would find, insert batteries, and follow the beeping to find the next stop. Imagine the strong feeling of straying in the middle of the night in an unknown terrain far away from civilization trusting only a beeping thing you found. That was the feeling I wanted to achieve.”
The Navigation Things (there are six in total) guide users to fixed waypoints with GPS, a digital compass, and a ring of WS2812 LEDs — but the primary means of feedback to the user is a beeping that gets faster as you approach the destination. [Jan] had only four days to make all six units, which was doable. But as most of us know, delivering on a tight deadline is often less about doing the work you know about, and more about effectively handling the unexpected obstacles that inevitably pop up in the process.
A lot of us make circuit boards at home. I find it a useful skill to have in my bag of tricks for intermediate steps along the way to a finished project, even if the finished version is going to be sent out to a PCB fab. When I need a breakout board that meshes with other development tools, for instance, there’s nothing like being able to whip something up that plugs right in. Doing it quickly, and getting on with the rest of the project instead of placing an order and waiting for delivery, helps keep me in the flow.
Toner transfer is by far the fastest way to make a circuit board at home — simply print the circuit out on a laser printer, iron it onto the copper, and etch. When it works, it’s awesome. When it doesn’t, it can be a hair-pulling exercise in figuring out which of myriad factors are misaligned.
For a long time now, I’ve been using a method that’s very reliable and repeatable. Recently, I’ve been tweaking a bit on the performance of the system, and I thought I’d share what I’ve got. At the moment, I’m able to very reliably produce boards with 6 mil (0.15 mm) traces and 8 mil (0.20 mm) spacing. With a little care in post-production, 4 mil / 6 mil is entirely plausible.
Building your own smartwatch is a fun challenge for the DIY hobbyist. You need to downsize your electronics, work with SMD components, etch your own PCBs and eventually squeeze it all into a cool enclosure. [Igor] has built his own ESP8266-based smartwatch, and even though he calls it a wrist display – we think the result totally sells as a smartwatch.
His design is based on a PCB for a wireless display notifier he designed earlier this year. The design uses the ESP-12E module and features an OLED display, LEDs, tactile switches and an FT232R USB/UART interface. Our beloved TP4056 charging regulator takes care of the Lithium-ion cell and a voltage divider lets the ESP8266’s ADC read back the battery voltage. [Igor] makes his own PCBs using the toner transfer method, and he’s getting impressive results from his hacked laminator.
Together with a hand-made plastic front, everything fits perfectly into the rubber enclosure from a Jelly Watch. A few bits of Lua later, the watch happily connects to a WiFi network and displays its IP configuration. Why wouldn’t this be a watch? Well, it lacks the mandatory RTC, although that’s easy to make up for by polling an NTP time server once in a while. How would our readers classify this well-done DIY build? Let us know in the comments!
One of the most popular methods of homebrew PCB fabrication is the toner transfer process. Compared to UV-sensitive films and CNC mills, the toner transfer process is fantastically simple and only requires a laser printer. Being simple doesn’t mean it’s easy, though, and successful toner transfer depends on melting the toner to transfer it from a piece of paper to a copper clad board.
This is heatless toner transfer for PCB fabrication. Instead of using a clothes iron or laminator to transfer toner from a paper to board, [simpletronic] is doing it chemically using acetone and alcohol.
Acetone usually dissolves laser printer toner, and while this is useful for transferring a PCB from paper to board, it alone is insufficient. By using a mixture of eight parts alcohol to three parts acetone, [simpletronic] can make the toner on a piece of paper stick, but not enough to dissolve the toner or make it blur.
From there, it’s a simple matter of putting a piece of paper down on copper clad board. After waiting a few minutes, the paper peels off revealing perfectly transferred board art. All the usual etching techniques can be used to remove copper and fabricate a PCB.
This is an entirely novel method of PCB fabrication, but it’s not exactly original. A few days ago, we saw a very similar method of transferring laser printed graphics to cloth, wood, and metal. While these are probably independent discoveries, it is great evidence there are still new techniques and new ways of doing things left to be discovered.
Thanks [fridgefire] for the tip.
The toner transfer process of producing PCBs has evolved tremendously over the last few years. It started out by printing PCB layouts onto magazines with a laser printer, then some clever people figured out that glossy inkjet photo paper would work just as well. Now there’s a new substrate for you – packing tape – and it seems to work pretty well.
[David] was designing a cheap board for a robot kit for a workshop and needed 100 tiny PCBs. They were simple boards, and perfectly suited for home PCB manufacturing. He started off by printing directly onto glossy magazine paper, but this wasn’t an ideal solution. During one run, some of the toner landed on the packaging tape he was using to secure the boards. A bit of serendipity came into play and [David] discovered packaging tape is usable in the toner transfer process.
The technique is simple enough: put some packaging tape on a piece of paper, print a board layout (reversed!) on a laser printer, and go through the usual clothes iron/laminator/etching process. [David] is actually using a hair straightener for transferring the toner over to the copper clad board – interesting, and in a pinch you can use the same tool for reflowing SMD components.