Fortunately (or unfortunately), [ucDude] has had the opportunity to try out a high quality video microscope while soldering some small surface mount components. He loved it, the problem was he had a hard time going back to using just his eyes. He wanted a video microscope but the cost for a professional one could not be justified. The solution? Build one!
[ucDude] called on one of his photographer friends to help. After discussing the project they decided to use a webcam and a lens from an SLR camera. Testing with the webcam resulted in an image that could not be zoomed-in enough, plus having to connect it to an external computer proved to be a bulky solution. They next tried a Raspberry Pi, camera module and zoom monocular. It worked great! The entire assembly was then mounted to a camera boom stand making it easy for the camera to be positioned over the work area and out of the way of hands and soldering irons. The Raspberry Pi’s HDMI output is plugged straight into an HD monitor. The result is exactly what [ucDude] was looking for. Now he can quickly and confidently solder his surface mount circuit boards.
My introduction to electronic manufacturing was as a production technician at Pennsylvania Scale Company in Leola PA in the early 1980’s. I learned that to work on what I wanted to work on I had to get my assigned duties done by noon or thereabouts. The most important lesson I had learned as a TV repairman, other than not to chew on the high voltage cable, was to use your eyes first. I would take a box of bad PCB’s that were essentially 6502 based computers that could count and weigh, and first go through inspecting them; usually the contents were reduced 50% right off by doing this. Then it was a race to identify and fix the remaining units and to keep my pace up I had to do my own desoldering.
It worked like this; you could set units aside with instructions and the production people would at some point go through changing components etc. for you or you could desolder yourself. I was pretty good at hand de-soldering 28 and 40 pin chips using a venerable Soldapulit manual solder sucker (as they were known). But to really cook I would wait for a moment when the production de-soldering machine was available. There was one simple rule for using the desoldering station: clean it when done! Failure to do so would result in your access to the station being suspended and then you might also incur the “wrath of production” which was not limited to your lunch bag being found frozen solid or your chair soaked in defluxing chemicals.
Pick and Place machines are one of the double-edged swords of electronics.They build your boards fast, but if you don’t have everything setup perfectly, they’ll quickly make a mess. A pick and place can’t grab a resistor from a pile and place it – so far only humans can pull that one off. They need parts organized and oriented in reels or trays.
[Parker Dillmann] had to load some parts, but didn’t have a tray for them, so he 3D printed his own. [Parker] works at a small assembly house in Texas. He’s working on a top secret design which includes FFC connectors. Unfortunately, the connectors shipped in pick and place unfriendly tubes rather than reels. If he couldn’t find a tray, [Parker] would have to hand place those connectors as a second operation, which would increase the time to build each board and leave more chances for mistakes.
Rather than place each part by hand, [Parker] got in touch with his friend [Chris Kraft] who is something of a 3D printing guru. [Chris] confirmed that a 3D printed tray would be possible, though the PLA he prints with was not static safe. That was fine for the connectors, but [Parker] was hoping to save some tray space by putting his PSOC4 chips in the printed tray as well.
[Parker] used SketchUp to design a tray that would fit his Madell DP2006-2 pick and place. He left .15mm clearance around the parts – just enough to cover any inaccuracies during printing, but not enough to throw off parts placement. He sent the STL file over to [Chris] who used Simplify3D to a create a Gcode file. [Chris] printed the tray at .2 mm layer height on his MakerGear M2 printer, and the results looked great. Would they be good enough for the pick and place machine?
[Parker] received the printed trays in the mail and loaded them with parts. The pick and place had no problem finding and placing the connectors, making this job a huge success. [Parker] even left room for the PSOC4 chips.He plans to paint the tray with anti-static paint before giving them at try.
[Matt] wanted his own light saber. You could argue that this is nearly as dangerous since you can’t see the beam and it doesn’t end a few feet past the business end of the grip. Plus there’s that who “not actually a Jedi” thing.
We don’t know if retro computing fans are going to love or hate this (translated). On the one hand it’s pretty cool to see a ZX81 clone up and running. On the other hand, an Amiga 600 case was sacrificed to serve as the body for the hack. [Thanks Juan]
Watchdog timer. If you know what that is your mind immediately says “good idea” when you hear the word. If you don’t know, you need to learn. Watchdogs are reset timers that are built into most microcontrollers. If your firmware gets stuck and doesn’t maintain the timer’s counter at a regular interval the watchdog it will perform a hardware reset and hopefully your hardware will start functioning again. Here’s a guide for using the watchdog in an Arduino, but the concepts are pretty much universal.
And finally, if you’re struggling with surface mount soldering we recommend grabbing two soldering irons. But in a pinch just grab some heavy gauge copper wire and wrap it around your soldering iron tip. It ends up being a two-point soldering iron set for the size of specific components such as 0805 resistors. [Thanks Rupert]
Populating a large surface mount PCB can take forever. [craftycoder] from Freeside Atlanta has built a great looking manual pick and place machine, removing the need for tweezers. No more will passives stick to your tweezers while you are trying to place them on your PCB!
We have seen a lot of pick and place machines in the past few years. What makes this one stand out is its simplicity and the no-nonsense build. This pick and place is built on an MDF platform, uses bearings from Amazon, standard 12 mm rails, and has a small camera for a close-up look at your part placement. Sure it is a manual method, but it beats painstakingly placing each part with tweezers. It would be interesting to see how much this entire build cost; we expect that it was not too expensive. See this thing in action in the video after the break.
Has reflowing surface mount components got you down? [Giorgos] is currently working on a project that will lift your spirits…. well at least your hot air gun. Tired of manually holding his heat gun in one hand and IR thermometer in the other, [Giorgos] set out to create a device to alleviate just that. Although not completed yet, it appears the machine’s intent is to hold the heat gun at an appropriate height above the work piece in order to achieve the correct reflow temperature. He doesn’t say how the height of the hot air gun will be controlled. We’d like to see a microcontroller adjust the height of the hot air gun depending on the temperature of the component to be reflowed. [Giorgos] gives an extremely detailed account of his build process. Make sure to check out all four pages of the project post!
He had tried using hacked together equipment, but after encountering a range of issues he finds the investment in a few key items saves time and money in the long run. The first is a precision tooling fixture block; that metal plate with a grid of holes that makes up the background of the image above. It comes with machined pegs which fit the holes perfectly, and as you can see, his panel of 16 boards include tooling holes that line up with the fixture. Once in place, a steel solder stencil is aligned with the board using its own tooling holes. The alignment of the stencil and its uniformed thickness ensure that the perfect amount of solder paste is easy to apply with a squeegee. [Zach] hand places his components but he did invest in a proper reflow oven to make the soldering a set and forget process.