There are a ton of ways to go about building your own reflow oven. Most of these builds start with, well, an oven — usually a toaster oven — with a small but significant minority choosing to modify a hotplate. But this might be the first time we’ve seen a waffle iron turned into a reflow oven.
Of course, what [Vincent Deconinck] came up with is not an oven per se. But his “RefloWaffle” certainly gets the job done. It started with an old waffle maker and a few experiments to see just how much modification it would take to create the various thermal reflow profiles. As it turned out, the original cooking surfaces had too much thermal inertia, so [Vincent] replaced them with plain copper sheets. That made for quicker temperature transitions, plus created some space between the upper and lower heating elements for the SMD board.
As for control, [Vincent] originally used an Arduino with a relay and a thermocouple, but he eventually built a version 2.0 that used a hacked Sonoff as both controller and switch. Adding the thermocouple driver board inside the Sonoff case took a little finagling, but he managed to get everything safely tucked inside. A web interface runs on the Sonoff and controls the reflow process.
We think this is a great build, one that will no doubt see us trolling the thrift stores for cheap waffle irons to convert. We’ve seen some amazing toaster oven reflows, of course, but something about the simplicity and portability of RefloWaffle just works for us.
SD cards have long been a favorite with microcontroller hobbyists. Cheap, readily available, and easily interfaced, they remain a staple for small projects that need to store a lot of data. Now, they’re available in chip form! These are known as SD NAND parts that emulate the SD card interface itself.
[LadyAda] recently gave them a test-drive after spotting a tweet from [Greg Davill] (who we’re familiar with thanks to his excellent LED cubes). The devices are manufactured by XTX Technology and available from LCSC in a range of 1, 2, 4, and 8 GB sizes. [Ivan Grokhotkov] also illuminated a similar device from another maker in a reply to [Greg’s] original tweet, so there may be more sources out there.
These chips come in standard LGA8 surface mount package and can be easily soldered to a board, offering mechanical and manufacturing benefits versus using a normal SD or microSD card in a slot-type connector. Also, unlike other SMD flash memory parts, they handle all the file system details and wear levelling for you! With the inflation of SD card sizes, it’s also difficult to find these on the shelf in normal cards these days.
[Adafruit] plan to have a breakout for these parts out soon with a level shifter included for ease of use. We can imagine these chips finding their way into all manner of datalogger projects, since they can be ordered with other parts and permanently soldered into a design. If you’ve got a particularly good idea where these chips would prove useful, sound off in the comments. Video after the break.
Continue reading “New Part Day: SD NAND Are Surface Mount Chips That Work Like An SD Card”
With reflow soldering, sometimes close is good enough. At the end of the day, the home gamer really just needs a hot plate or an old toaster oven and a calibrated Mark I eyeball to get decent results. This exhaust fan-equipped reflow oven is an attempt to take control of what’s perhaps the more challenging part of the reflow thermal cycle — the cool down.
No fan of the seat-of-the-pants school of reflow soldering, [Nabil Tewolde] started with a cast-off toaster oven for what was hoped to be a more precise reflow oven. The requisite temperature sensors and solid-state relays were added, along with a Raspberry Pi Zero W and a small LCD display. Adding the cooling assist started by cutting a gaping hole cut in the rear wall of the oven, which was then filled with a short stretch of HVAC duct and a stepper-controlled damper. The far end of the duct was fitted with a PC cooling fan; while it seems sketchy to use a plastic fan to eject hot air from the oven, [Nabil] says the exhaust isn’t really that hot by the time it gets to the fan. At the end of the reflow phase of the thermal profile, the damper opens and the fan kicks on, rapidly cooling the oven’s interior.
Unfortunately, [Nabil] still needs to crack open the oven door to get decent airflow; seems like another damper to admit fresh air would help with that. That would complicate things a bit, but it still wouldn’t be as over-the-top as some reflow builds we’ve seen. Then again, that calibrated eyeball thing can work pretty well too, even without a toaster oven.
Continue reading “Exhaust Fan-Equipped Reflow Oven Cools PCBs Quickly”
Skills challenges have become a fun way to facilitate friendly competition amongst anyone who appreciates a fine solder joint. If you’ve seen any Supercon / Remoticon coverage there’s surely been a mention of the infamous soldering skills challenge, where competitors test their mettle against surface mount components sized to be challenging but fair. What if there was a less friendly SMD challenge designed to make you hold your breath lest you blow the components away? Well now there is, the SMD Challenge Extreme Edition by friend-of-the-Hackaday and winner of the 2019 Supercon soldering challenge [Freddie].
When assembled the SMD Extreme Edition uses a 555 timer and a 74HC4017 decade counter to light a ring of 10 LEDs lights around its perimeter, powered by a coin cell. However the Extreme Edition deviates from the typical SMD Challenge format. Instead of ramping up in difficulty with ever-shrinking components, the Extreme Edition only has one size: torturous. See those gray blobs in the title image? Those are grains of rice.
The Extreme Edition’s 0201-sized LEDs aren’t the absolute smallest components around, but to minimize enjoyment all passives are 01005. (Check out the SMD Challange Misery Edition for even 01005 LED action.)
The Extreme Edition has other tricks up its sleeve, too. That 555 may be venerable in age, but this version is in an iron-frustrating 1.41 x 1.43 mm BGA package, which pairs nicely with that decade counter in 2.5 mm x 3.5 mm QFN.
Despite the wordwide pandemic locking down travel and conferences, a few brave challengers have already taken up their iron and succeeded at Extreme SMD. Want to see it in action? Check out the original Tweets after the break.
Continue reading “SMD Challenge Extreme Edition Gets Our Flux Flowing”
Oregon State University must be a pretty good place to go to school if you want to hack on robots. Their robotics club, which looks active and impressive, has a multi-part video series on how to solder surface mount components that is worth watching. [Anthony] is the team lead for their Mars Rover team and he does the job with some pretty standard-looking tools.
The soldering station in use is a sub-$100 Aoyue with both a regular iron and hot air. There’s also a cheap USB microscope that looks like it has a screen, but is covered in blue tape to hold it to an optical microscope. So no exotic tools that you’d need a university affiliation to match.
Continue reading “Robotics Club Teaches Soldering”
If you need to add one or two SMT chips to your breadboarded prototype, [Travis Hein] has you covered. He designed a set of small SMD adaptor boards for various SOIC, SOT23, and DPAC patterns using KiCad. He has released them as open source, so you can feel free to use them or modify them as needed.
Normally we don’t see people bypassing the schematics when designing a PCB. But we can agree that [Travis] has found a situation where going direct to PCB makes more sense. He just plops down the package in Pcbnew, adds some pin headers and wires everything up directly on the PCB. (But don’t worry, some of you may remember [Travis] from his earlier SSR mains switching project, which demonstrates that he can indeed draw proper schematics.) We know there are more people out there who prefer to go straight to PCB layout… [mikeselectricstuff] comes to mind. If you could yourself among this tribe, let use know your reasoning in the comments below.
We wrote about a similar universal breakout boards for SMD parts back in 2016, which is a single breakout board for two- and three-pin jelly-bean components. If you paired some of those boards with [Travis]’s breakout boards, it would make a great combination to keep in your prototyping gadgets bin. Consider this project the next time your favorite PCB shop has a sale.
[Kadah]’s solution for storing short tapes of SMT parts is as attractive as it is clever. The small 3D-printed “tape reels” can double as dispensers, and stack nicely onto each other thanks to the sockets for magnets. The units come in a few different sizes, but are designed to stack in a consistent way.
We love the little touches such as recessed areas for labels, and the fact that the parts can print without supports (there are a couple of unsupported bridges, but they should work out fine.) Also, the outer dimensions of the units are not an accident. They have been specifically chosen to nestle snugly into the kind of part drawers that are a nearly ubiquitous feature of every hardware hacker’s work bench.
STLs are provided for handy download but [Kadah] also provides the original Fusion 360 design file, with all sizes defined as easily-customized parameters. In addition, [Kadah] thoughtfully provided each model in STEP format as well, making it easy to import and modify in almost any 3D CAD program.
Providing 3D models in STEP format alongside STLs is nice to see, because it gives more options to people if things need some tweaking, because editing the STL file can be done if needed, but isn’t optimal. Thankfully the ability to export STEP files is still open to hobbyists using Fusion 360, since Autodesk decided to leave that feature available to personal use licenses.