UV Light Box Cures Both Sides of a PCB

[GiorgiQ] needed a UV light to cure the etch resist on his printed circuit boards, and what better way to accomplish this than to build the perfect UV light box himself? The box consists of a custom PCB (of course) featuring a pair of 12V relays tripping quad 9×12 matrices of 400nm UV LEDs, with a total of 432 diodes in use — not to mention resistors to protect the LEDs. All of it is run by an Arduino Nano.

The enclosure is made out of 12mm MDF and 3mm cast acrylic, and the circuit board fits into a tray …read more http://pje.fyi/Q0W66Z

Paul Jacob Evans


The Clutter Manifesto

My basement workshop is so crammed full of stuff I literally can’t use it. My workbench, a sturdy hardwood library table, is covered in junk to the point that I couldn’t find a square foot that didn’t have two layers of detritus on it — the top layer is big things like old projects that no longer work, boxes of stuff, fragile but light things perched on top. Underneath is the magma of bent resistors, snippets of LED strip, #4 screws, mystery fasteners I’ll never use, purple circuit boards from old versions of projects, and a surprising number of SparkFun …read more http://pje.fyi/Q0Hx2B

Paul Jacob Evans

IoT with the Ethereum Blockchain

Anyone keeping up with financial news today is surely inundated with stories about Bitcoin and other cryptocurrencies. While most of the news is about the potentially inflated value of some of these coins, and how drastically they have changed in price in just a decade, there are other interesting things going on behind the scenes. For example, the currency Ethereum allows for a distributed programming platform of sorts to be implemented in the blockchain, which [GusGorman402] has taken advantage of in his latest project (YouTube link, embedded below).

The device that he built is based on an ESP8266 which connects …read more http://pje.fyi/Q04dhF

Paul Jacob Evans

Repair Job Fixes Compressor, Gets in Online

We’ll never cease to be amazed at the things people try to put on the Internet of Things. Some are no-brainers, like thermostats, security cameras, and garage door openers. Others, like washing machines and refrigerators, are a little on the iffy side, but you can still make a case for them. But an IoT air compressor? What’s the justification for such a thing?

As it turns out, [Boris van Galvin] had a pretty decent reason for his compressor hacks, and it appears that the IoT aspect was one of those “why not?” things. Having suffered the second failure of his …read more http://pje.fyi/PzLy9w

Paul Jacob Evans

The Most Useless Tools You Can’t Seem to Part With

I’m a tool person. No matter how hard I try, I eventually end up with a bunch of tools that I just can’t bear to banish from my workshop. Why? I’m gonna keep it 100%: it’s the same emotion behind hoarding — fearing that you might need a thing later and not be able to have it.

The stuff costs money, and if you have to script to buy a bunch of tools pertaining to Project X, you expect to still have and probably need those very same tools — even if they have to sit in a box on …read more http://pje.fyi/PxmVB5

Paul Jacob Evans

Rescuing An Antique Saw Set

Who doesn’t like old tools? Even if they aren’t practical to use for production, plenty of old tools still have a life to offer the hobbyist or home worker.  Some tools might seem a bit too far gone – due to age, rust, or practicality, to use. That’s where [Hand Tool Rescue] comes in. [HTR] finds rusty, dirty old tools, and brings them back to life. Sometimes they’re practical tools, other times, they’re a bit out there. In a recent video, he restored a BeMaCo automatic saw set from the 1940’s. Saw sets are tools which bend each tooth of …read more http://pje.fyi/PwLqzq

Paul Jacob Evans

Not Your Typical ATX Bench PSU

We know what you’re thinking — yet another scrap PC power supply turned into a bench PSU. But look a little closer and you’ll see a nicely designed linear bench supply that just fits inside a gutted ATX case.

A lot of the items on [Medzik]’s BOM for this build are straight from the scrap bin. The aforementioned ATX supply case is one, as is the power transformer donated by a friend. Modules such as the 30V/2A regulator, the digital volt/ammeter, and a thermostat module to control the fan at higher power settings were all sourced via the usual suspects. …read more http://pje.fyi/PvXQFf

Paul Jacob Evans