WWII Aircraft Radio Roars To Life: What It Takes To Restore A Piece Of History

December 12, 2019 by 59 Comments

I’ve been told all my life about old-timey Army/Navy surplus stores where you could buy buckets of FT-243 crystals, radio gear, gas masks, and even a Jeep boxed-up in a big wooden crate. Sadly this is no longer the case. Today surplus stores only have contemporary Chinese-made boots, camping gear, and flashlights. They are bitterly disappointing except for one surplus store that I found while on vacation in the Adirondacks: Patriot of Lake George.

There I found a unicorn of historical significance; an un-modified-since-WW2 surplus CBY-46104 receiver with dynamotor. The date of manufacture was early-war, February 1942. This thing was preserved as good as the day it was removed from its F4F Hellcat. No ham has ever laid a soldering iron or a drill bit to it. Could this unit have seen some action in the south Pacific? Imagine the stories it could tell!

My unconventional restoration of this radio followed strict rules so as to minimize the evidence of repair both inside and out yet make this radio perform again as though it came fresh off the assembly line. Let’s see how I did.

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Used EDM Electrodes Repurposed As Air Bearings For Precision Machine Tools

November 18, 2019 by 14 Comments

If you’ve ever played air hockey, you know how the tiny jets of air shooting up from the pinholes in the playing surface reduce friction with the puck. But what if you turned that upside down? What if the puck had holes that shot the air downward? We’re not sure how the gameplay would be on such an inverse air hockey table, but [Dave Preiss] has made DIY air bearings from such a setup, and they’re pretty impressive.

Air bearings are often found in ultra-precision machine tools where nanometer-scale positioning is needed. Such gear is often breathtakingly expensive, but [Dave]’s version of the bearings used in these machines are surprisingly cheap. The working surfaces are made from slugs of porous graphite, originally used as electrodes for electrical discharge machining (EDM). The material is easily flattened with abrasives against a reference granite plate, after which it’s pressed into a 3D-printed plastic plenum. The plenum accepts a fitting for compressed air, which wends its way out the micron-sized pores in the graphite and supports the load on a thin cushion of air. In addition to puck-style planar bearings, [Dave] tried his hand at a rotary bearing, arguably more useful to precision machine tool builds. That proved to be a bit more challenging, but the video below shows that he was able to get it working pretty well.

We really enjoyed learning about air bearings from [Dave]’s experiments, and we look forward to seeing them put to use. Perhaps it will be in something like the micron-precision lathe we featured recently.

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Takata Airbag Recalls Widen To Potentially Affect Other Types Of Airbag

November 7, 2019 by 55 Comments

The Takata airbag case has become the largest product recall in history, caused over 20 deaths, and cost many billions of dollars. Replacement efforts are still ongoing, and sadly, the body count continues to rise.  Against this backdrop, further recalls have been announced affecting another type of Takata airbag.

The recall affects BMW 3 Series vehicles, produced between 1997 and 2000. Notably, it appears these cars may have been built before Takata’s fateful decision to produce airbag inflators using ammonium nitrate propellants, known for their instability. Instead, these vehicles likely used Takata’s proprietary tetrazole propellant, or Non-Azide Driver Inflators (NADI). These were developed in the 1990s, and considered a great engineering feat at the time. They were eventually phased out around 2001 for cost reasons, leading to the scandal that rolls on to this day.

As these airbags were produced before the switch to ammonium nitrate, they have thus far escaped scrutiny as part of existing recalls. Two recent incidents of airbag misdeployments in Australia led to the recall, causing a death and a serious injury. BMW Australia have advised owners not to drive affected vehicles, and are offering loan or hire cars to affected vehicles. Given the age of the affected vehicles, the company is considering a buyback program in the event that suitable replacement parts cannot be made available.

This development is foreboding, as it suggests yet more cars, originally considered safe, are now at risk of injuring or killing occupants in the event of a crash. It’s not yet clear exactly which makes are effected by this recall, but expect the numbers of vehicles to continue to climb.

[via Sydney Morning Herald]

The 3D Printers, Scanners, And Art Robots Of Maker Faire Rome

November 2, 2019 by 7 Comments

How is it possible that a robot can sketch both better and worse than I can at the same time, and yet turn out an incredible work of art? Has 3D-scanning really come so far that a simple camera and motorized jig can have insane resolution? These are the kinds of questions that were running through my mind, and being answered by the creators of these brilliant machines, at Maker Faire Rome.

There was a high concentration of robots creating art and 3D printing on display and the Faire, so I saved the best examples just for this article. But you’ll also find hacks from a few groups of clever students, and hardware that made me realize industrial controllers can be anything but boring. Let’s take a look!

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High-Precision Air Bearing CNC Lathe And Grinder

October 31, 2019 by 27 Comments

You know you’re in for a treat when you are told that a lathe which can reach a resolution of one micrometer (1×10−6, a millionth of a meter, or 0.00004″ for people who love zeros) is ‘not hard to build’.  This is one of the opening statements in this video by [Dan Gelbart], as he walks the viewer through the details of a custom CNC lathe which he built. (Video embedded below.)

As it’s a combined CNC lathe and grinder, it uses custom software he had developed specifically for the machine. Much of the high precision of the machine is courtesy of air bearings. All but two of the air bearings were made by [Dan], with the two surplus air bearings he used coming from machines used in the semiconductor industry.

The bed of the machine is formed out of off-the-shelf reference granite, to which the other parts are epoxied, providing a stable base with well-defined dimensions. Though perhaps a few light years beyond most DIY lathe efforts, [Dan]’s videos nevertheless provide a treasure trove of tips and information for lathe builders and users alike. Certainly worth a look.

Thanks [Drew] for the tip in the comments.
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Amstrad Portable Gets A Modern LCD Transplant

October 30, 2019 by 5 Comments

Playing classic games on the real hardware is an experience many of us enjoy, but sometimes the hardware is just a bit too retro for modern sensibilities. A case in point is the miserable monochrome LCD that was originally installed in the Amstrad PPC640 portable 8086 PC that [Drygol] recently picked up. He decided that his portable Amstrad sessions would be far more enjoyable if he swapped it out for a display that didn’t have 30+ years on the clock.

To quell the complaints of any of the vintage hardware aficionados out there, it’s worth mentioning that the original LCD was actually damaged and needed to be replaced anyway. Granted [Drygol] could have tried to find a contemporary panel to replace it with, but looking at the incredible before and after shots of the modded PPC640, it’s hard to argue he didn’t make the right decision by throwing a modern display into the otherwise largely original computer.

Getting the new LCD’s PCB ready for installation.

[Drygol] says he picked up a cheap 4:3 LCD TV on eBay, and as luck would have it, found that the new panel dropped perfectly into the original frame. Getting it buttoned back up required the removal of the RF can and all the female connections on the TV’s PCB, plus he had to cut some holes in the back of the display enclosure to mount the LCD’s controls, but overall it looks very stock.

Of course, getting the new LCD display in the original frame was only half the battle, it still needs to be connected up to the computer somehow. To get everyone playing nicely with each other, [Drygol] is using a commercially available MDA/CGA/EGA to VGA converter that is installed where the batteries would have gone originally. Wired to the PPC640’s external monitor connector, it allows him to drive the new display without having to use the original LCD interface.

[Drygol] has made something of a name for himself by performing some of the most impressive restorations and modifications of retro hardware in recent memory. From the unbelievable work that went into repairing a smashed Atari 800XL case to his gorgeous custom Amiga A500, his projects are sure to please the retro hardware lovers in the audience.

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Giant LEDs, Ruby Lasers, Hologram Displays, And Other Cool Stuff Seen At Maker Faire Rome

October 25, 2019 by 16 Comments

Hackers from all over Europe descended upon Rome last weekend for the Maker Faire that calls itself the “European Edition”. This three-day event is one of the largest Maker Faires in the world — they had 27,000 school students from all over Italy and Europe attend on Friday alone.

This was held at Fiera Roma, a gigantic conference complex two train stops south of the Rome airport — kind of in the middle of nowhere. I was told anecdotally that this is the largest event the complex hosts but have no data to back up that claim. One thing’s for certain, three days just wasn’t enough for me to enjoy everything at the show. There was a huge concentration of really talented hardware hackers on hand, many who you’ll recognize as creators of awesome projects regularly seen around Hackaday.

Here’s a whirlwind tour of some of my favorites. On that list are a POV holographic display, giant cast-resin LEDs, an optical-pump ruby laser built out of parts from AliExpress, blinky goodness in cube-form, and the Italian audience’s appreciation for science lectures (in this case space-related). Let’s take a look.

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