Strap on the jeweler’s loupe and lay off the caffeine for a few days. You’ll need to be at your peak for the SMD Soldering Challenge at this year’s DEF CON (number 26 for those counting).
It’s exciting to see that a Soldering Skills Village has been added to the conference this year. It will be in the same room as the Hardware Hacking Village. After all, who doesn’t want to solder at a conference? This soldering challenge is a great way to ring in the new village, and will take place in eight heats of six people for a total of 48 contestants. If you want to compete, make sure you get to the village right away and sign up for a slot!
A familiar board is being used for the contest. It’s the SMD Challenge board which MakersBox developed. You can check out the Hackaday.io project page and even order one from their Tindie store if you like. The contest will be scored based on time, completion, functionality, precise orientation, and quality of the joints.
The SOIC ATtiny85 is a snap to place on the board, but things get harder with each step. To successfully complete it you need to solder both a resistor and an LED in 1206, 0805, 0603, 0402, and 0201 packages. Those oh-two-oh-ones are basically grains of sand… good luck with that! We’re really excited that MakersBox rolled some custom Hackaday and Tindie boards (pictured above) for this contest which we’re honored to sponsor. It sounds as if the winners will be announced during Hackaday and Tindie’s traditional Breakfast at DEF CON which is happening at 10:30am on Sunday in the HHV.
We plan to spectate during some of the heats and if you’re at the con you should too! For those participating, here’s our advice. Practice soldering the smallest of parts ahead of time (watch some videos on it at the very least). Bring a multimeter to test the diode polarity because you won’t be able to see the symbols on the smallest parts. You may even consider bringing some custom tools; this surface mount “clamp” comes to mind, you’ll just need a much smaller version.
If you have advice of your own, we’d love to hear it in the comments below!
Surface mount is where the action is in the world of DIY PCBs, and deservedly so. SMDs are so much smaller than through-hole components, and fewer holes to drill make surface-mount PCBs easier to manufacture. Reflow soldering is even a snap now thanks to DIY ovens and solder stencils you can get when you order your boards.
So what’s the point of adding another stencil to the surface-mount process? These component placement stencils are [James Bowman]’s solution for speeding up assembly of boards in production runs too small to justify a pick and place robot. [James] finds that placing small components like discrete resistors and caps easy, but struggles with the placement of the larger components, like QFN packaged microcontrollers. Getting such packages lined up exactly is hard when the leads are underneath, and he found repositioning led to smeared solder paste. His acrylic stencils, which are laser-cut from SVGs derived directly from the Eagle files with a script he provides, sandwich the prepped board and let him just drop the big packages into their holes. The acrylic pops off after placement, leaving the components stuck to the solder paste and ready for their trip to the Easy Bake.
[James] claims it really speeds up hand placement in his biggish runs, and it’s a whole lot cheaper than a dedicated robot. But as slick as we think this idea is, a DIY pick and place is still really sweet.
Most of us have made the transition from through hole parts to surface mount. There are lots of scattered tutorials, but if you want to learn some techniques or compare your technique to someone else’s, you might enjoy [Moto Geek’s] hour-long video on how he does surface mount with reflow soldering. You can see the video below.
What makes the video interesting is that it is an hour long and covers the gamut from where to get cheap PCBs, to a homebrew pick and place pencil. [Moto Geek] uses a stencil with solder paste, and he provides links to the materials he uses. Continue reading “An Hour to Surface Mount”
Ever wonder what’s inside a surface-mount inductor? Wonder no more as you watch this SMT inductor teardown video.
“Teardown” isn’t really accurate here, at least by the standard of [electronupdate]’s other component teardowns, like his looks inside LED light bulbs and das blinkenlights. “Rubdown” is more like it here, because what starts out as a rather solid looking SMT component needs to be ground down bit by bit to reveal the inner ferrite and copper goodness. [electronupdate] embedded the R30 SMT inductor in epoxy and hand lapped the whole thing until the windings were visible. Of course, just peeking inside is never enough, so he set upon an analysis of the inductor’s innards. Using a little careful macro photography and some simple image analysis, he verified the component’s data sheet claims; as an aside, is anyone else surprised that a tiny SMT component can handle 30 amps?
Looking for more practical applications for decapping components? How about iPhone brain surgery?
Continue reading “What Lies Within: SMT Inductor Teardown”
Have you ever wanted to build your own Arduino from scratch? [Pratik Makwana] shares the entire process of designing, building and flashing an Arduino Nano clone. This is not an entry-level project and requires some knowledge of soldering to succeed with such small components, but it is highly rewarding to make. Although it’s a cheap build, it’s probably cheaper to just buy a Nano. That’s not the point.
The goal here and the interesting part of the project is that you can follow the entire process of making the board. You can use the knowledge to design your own board, your own variant or even a completely different project.
[Pratik Makwana] starts by showing how to design the circuit schematic diagram in an EDA tool (Eagle) and the corresponding PCB layout design. He then uses the toner transfer method and a laminator to imprint the circuit into the copper board for later etching and drilling. The challenging soldering process is not detailed, if you need some help soldering SMD sized components we covered some different processes before, from a toaster oven to a drag soldering process with Kapton tape.
Last but not least, the bootloader firmware. This was done using an Arduino UNO working as master and the newly created the Arduino Nano clone as target. After that you’re set to go. To run an actual sketch, just use your standard USB to UART converter to burn it and proceed as usual.
Voilá, from zero to Nano:
Continue reading “From Zero to Nano”
What’s your favorite value of resistor? 1K? 10K? They’re all fine, but when you need nearly no resistance at all, nothing beats the good old zero-ohm resistor.
Wait a minute! Resistors are supposed to resist current. What the heck does a zero-ohm resistor do? Well, the short story (tee-hee!) is that it’s like a jumper for single-sided surface-mount boards. In the bad old days, companies used to save money by running single-sided boards, and you could buy wire jumpers to help make the layout that much easier.
Fast forward to the modern era, where there’s not a through-hole component to be seen. What’s the resistance (ideally) of a wire? Zero ohms. And thus the zero-ohm resistor was born. We have a whole spool of them in our closet in 1206, the largest SMD size that we use, in order to be able to sneak two or three tracks underneath, even on a home-etched board. They’re great.
Anyway, what set us off rhapsodizing about the lowest value resistor was this article on the peculiarities of the zero ohm resistor. Of course, nothing has zero resistance, and the article walks you through some of their real-world properties. Enjoy!
If you’re assembling prototypes of SMD boards on your own, placing the parts accurately can be a pain. Of course, it’d be nice to have a full pick and place machine, but those are rather expensive and time consuming to set up, especially for a small run of boards. Instead, a vacuum pickup tool can help you place the parts quickly and accurately by hand.
The folks over at Ohmnilabs have put together their own DIY pickup tool for about $75, and it’s become part of their in-house prototyping process. They grew tired of placing components with tweezers, which require you to remove parts from the tape before lifting them, and have a tendency to flip parts over at the worst time.
The build consists of a couple parts that can be bought from Amazon. An electric vacuum pump does the sucking, and the vacuum level is regulated with an adjustable buck converter. A solid foot switch keeps your hands free, and syringe tips are used to pick the parts up.
This looks like a simple afternoon build, but if you’re prototyping, it could save you tons of time. To see it in action, check out the video after the break.
Continue reading “A DIY Vacuum Pickup Tool for $75”