For the unfamiliar, a pummer is a device from the BEAM style of robotics, a sort of cyborg plant that absorbs solar energy during the day and turns it into a gently pulsating light that “pumms” away the dark hours.
[Mohit Bhoite]’s take on the pummer is an extraordinary model of a satellite executed mainly in brass rod. His attention to detail on the framework boggles our minds; we could work for days on a brass rod and never achieve the straight lines and perfect corners he did. The wings support two solar cells, while the hull of the satellite holds a dead-bugged 74HC240 octal buffer/line-driver chip and all the other pumm-enabling components. A one farad supercap – mounted to look like a dish antenna – is charged during the day and a single LED beacon blinks into the night.
No schematic is provided, but there are probably enough closeup shots to reverse engineer this, which actually sounds like a fun exercise. (Or you can cheat and fetch the PDF copy of the old Make magazine article that inspired him.)
For most of human industrial history, the blacksmith was the indispensable artisan. He could fashion almost anything needed, from a simple hand tool to a mechanism as complex as a rifle. Starting with the most basic materials, a hot forge, and a few tools that he invariably made himself, the blacksmith was a marvel of fabrication.
If you have any doubt how refined the blacksmith’s craft can be, feast your eyes on [Seth Gould]’s masterpiece of metalwork. Simply called “Coffer”, [Seth] spent two years crafting the strongbox from iron, steel, and brass. The beautifully filmed video below shows snippets of the making, but we could easily watch a feature-length film detailing every aspect of the build. The box is modeled after the strongboxes built for the rich between the 17th and 19th centuries, which tended to favor complex locking mechanisms that provided a measure of security by obfuscation. At the end of the video below, [Seth] goes through the steps needed to unlock the chest, each of which is filled with satisfying clicks and clunks as the mechanism progresses toward unlocking. The final reveal is stunning, and shows how much can be accomplished with a forge, some files, and a whole lot of talent.
If you’ve never explored the blacksmith’s art before, now’s the time. You can even get started easily at home; [Bil Herd] will show you how.
Late last year, artist [Steve Messam]’s project “Whistle” involved 16 steam engine whistles around Newcastle that would fire at different parts of the day over three months. The goal of the project was bring back the distinctive sound of the train whistles which used to be fixture of daily life, and to do so as authentically as possible. [Steve] has shared details on the construction and testing of the whistles, which as it turns out was a far more complex task than one might expect. The installation made use of modern technology like Raspberry Pi and cellular data networks, but when it came to manufacturing the whistles themselves the tried and true ways were best: casting in brass before machining on a lathe to finish.
The original whistles are a peek into a different era. The bell type whistle has three major components: a large bell at the top, a cup at the base, and a central column through which steam is piped. These whistles were usually made by apprentices, as they required a range of engineering and manufacturing skills to produce correctly, but were not themselves a critical mechanical component.
In the original whistle shown here, pressurized steam comes out from within the bottom cup and exits through the thin gap (barely visible in the image, it’s very narrow) between the cup and the flat shelf-like section of the central column. That ring-shaped column of air is split by the lip of the bell above it, and the sound is created. When it comes to getting the right performance, everything matters. The pressure of the air, the size of the gap, the sharpness of the bell’s lip, the spacing between the bell and the cup, and the shape of the bell itself all play a role. As a result, while the basic design and operation of the whistles were well-understood, there was a lot of work to be done to reproduce whistles that not only operated reliably in all types of weather using compressed air instead of steam, but did so while still producing an authentic re-creation of the original sound. As [Steve] points out, “with any project that’s not been done before, you really can’t do too much testing.”
Embedded below is one such test. It’s slow-motion footage of what happens when the whistle fires after filling with rainwater. You may want to turn your speakers down for this one: locomotive whistles really were not known for their lack of volume.
[Kevin] owns a benchtop CNC mill that has proven itself to be a capable tool, but after becoming familiar with some of its shortcomings, he has made a few modifications. In order to more efficiently hold and access workpieces on his custom fixturing table, he designed and made his own toe clamps and they look beautiful.
The usual way to secure a piece of stock to a fixturing table is to use top-down clamps, which hold the workpiece from the top and screw down into the table. However, this method limits how much of the stock can be accessed by the cutting tool, because the clamps are in the way. The most common way around this is to mount a vise to the table and clamp the workpiece in that. This leaves the top surface completely accessible. Unfortunately, [Kevin]’s benchtop Roland MDX-450 has a limited work area and he simply couldn’t spare the room. His solution was toe clamps, which screw down to the table and have little tabs that move inwards and downward. The tabs do the work of clamping and securing a piece of stock while maintaining a very low profile themselves.
The clamp bases are machined from stainless steel and the heads are brass, and the interface between the two is a set screw. Inserting a hex wrench and turning the screw moves the head forward or back, allowing a workpiece to be clamped from the sides with minimal interference. His design was done in Fusion 360 and is shared online.
On today’s episode of ‘this is a really neat video that will soon be demonetized by YouTube’ comes this fantastic build from [John]. It is the Golden Gun, or at least it looks like a Golden Gun because it’s made out of melted down brass casings. It’s a masterclass demonstration of melting stuff down and turning a thirteen-pound blob of metal into a two-pound precision machined instrument.
This build began by simply cutting a wooden block, packing it in sand, and melting approximately 1425 shell casings of various calibers in a DIY furnace. The molten brass was then simply poured into the open mold. This is standard yellow brass, with about 70% copper and 30% zinc. There’s a bit of aluminum in there from the primers, and the resulting block isn’t terribly great for machining. [John] says this could be fixed by adding a few percent of lead to the melt. To all the jokesters suggesting he add some unfired bullets to the melt, don’t worry, we already have that covered.
The machining went as you would expect it would with a large mill, but there are a few things that made this entire video worthwhile. For some of the holes, [John] had to square up the corners. The simplest and easiest way to do this is to break out a file. This is brass, though, and with some steel chisels hanging around the shop your mortise and tenon skills might come in handy. With the very careful application of force, [John] managed to put corners on a circle with a standard wood chisel. A bit later in the build video, a few more sharp corners were created by shoving a broach in the mill and jamming it down into the work.
When it comes to machining builds, this is high art. Yes, it’s the same as building an AR-15 out of a few hundred soda cans, but this one is made out of brass. It looks just great, and that final polish turns the entire project into something that looks like it’s out of a video game. Simply amazing.
Before the invention of the high-powered LED, and even really before the widespread adoption of electric lights in general, lighthouses still had the obligation of warning ships of dangers while guiding them into various safe harbors. They did this with gas lights and impressive glass lenses known as Fresnel lenses which helped point all available light in the correct direction while reducing weight and material that would otherwise be used in a conventional lens.
Now, a company in Florida is using acrylic in reproductions of antique Fresnel lenses. At first glance, it seems like acrylic might not be the best substitute for glass, but the company is able to achieve extreme precision using a CNC machine and then polishing and baking the acrylic which makes it transparent and excellent for use in lighthouse lenses like this. The reproduction lenses are built out of brass, and the lens elements are glued in place with a special adhesive. It’s a convincing replication worthy of use in any lighthouse.
Be sure to check out the video below to see how these lenses are built, and although we’re not entirely sure what exactly is being sprayed on the lenses when they are being polished, perhaps someone in the comments section can illuminate that for us. Of course, there are other uses for Fresnel lenses than in lighthouses, and we’ve seen some great examples of them put to use for many different applications.
Machinists are expected to make functional items from stock material, at least hat’s the one-line job description even though it glosses over many important details. [Eclix] wanted a birthday gift for his girlfriend that wasn’t just jewelry, indeed he wanted jewelry made with his own hands. After all, nothing in his skillset prohibits him from making beautiful things. He admits there were mistakes, but in the end, he came up with a recipe for two pairs of earrings, one set with sapphires and one with diamonds.
He set the gems in sterling silver which was machined to have sockets the exact diameter and depth of the stones. The back end of the rods were machined down to form the post for the clutch making each earring a single piece of metal and a single gemstone. Maintaining a single piece also eliminates the need for welding or soldering which is messy according to the pictures.