In the closing months of World War II, the Axis and the Allies were throwing everything they had at each other. The tide was turning to the Allies’ favor, but the Germans were showing a surprising resilience, at least in terms of replacing downed fighter and bomber aircraft. When the Allies examined the wreckage of these planes, they discovered the disturbing truth: the planes contained large pieces forged from single billets of metal, which suggested a manufacturing capability none of the Allies possessed and which allowed the Germans to quickly and cheaply make better and faster planes.
When the war was over, the Allies went looking for the tools the Germans had used to make their planes, and found massive closed-die forging presses that could squeeze parts out of aluminum and magnesium alloys in a single step. The Soviets carted off a 30,000 ton machine, while the Americans went home with a shipload of smaller presses and the knowledge that the Russians had an edge over them. Thus began the Heavy Press Program, an ultimately successful attempt by the US military to close a huge gap in strategic manufacturing capabilities that [Machine Thinking] details in the excellent video below.
One doesn’t instantly equate monstrous machines such as the Mesta 50,000-ton press, over nine stories tall with half of it buried underground and attached directly to bedrock, with airplane manufacture. But without it and similar machines that came from the program, planes from the B-52 to the Boeing 747 would have been impossible to build. And this isn’t dead technology by any means; sold to Alcoa in 1982 after having been operated by them for decades, the “Fifty” recently got a $100 makeover after cracks appeared in some castings, and the press and its retro-brethren are still squeezing out parts for fighters as recent as the F-35.
It’s easy to assume that older components will be less integrated and bulkier than we might otherwise expect. Then something seems ahead of its time, like the teeny-tiny 490IP1 LED which was produced in the former Soviet Union. [AnubisTTP] obtained and shared images of this tiny integrated single digit LED display in which the number measures a scant 2.5 mm tall; in production it was made easier to read with an external bubble lens magnifier clipped to the outside. The red brick the 490IP1 is pictured with is the Texas Instruments TIL306, a relatively normal sized DIP component with similar functionality.
The 490IP1 is called an intelligent LED display because the package contains a decade counter and driver circuitry for the integrated seven-segment LED digit, complete with a carry signal that meant multiple displays could be chained together. It is notable not just due to its size, but because the glass cover makes it easy to see the die inside, as well as the wire-bonded pads.
It’s always fascinating to see glimpses of the development path that display technologies took. It’s easy to take a lot of it for granted today, but back before technology was where it is now, all sorts of things were tried. Examples we’ve seen in the past include the fantastic (and enormous) Eidophor projector which worked by drawing images onto a rotating disk of oil with an electron gun. On the smaller end of things, the Sphericular display used optics and image masks to wring a compact 0-9 numerical display out of only a few lamps at the back of a box.
In an age of smartwatches, an analog watch might seem a little old-fashioned. Whether it’s powered by springs or a battery, though, the machinery that spins those little hands is pretty fascinating. Trouble is, taking one apart usually doesn’t reveal too much about their tiny workings, unless you get up close and personal like with this microscopic tour of an analog watch.
This one might seem like a bit of a departure from [electronupdate]’s usual explorations of the dies within various chips, but fear not, for this watch has an electronic movement. The gross anatomy is simple: a battery, a coil for a tiny stepper motor, and the gears needed to rotate the hands. But the driver chip is where the action is. With some beautiful die shots, [electronupdate] walks us through the various areas of the chip – the oscillator, the 15-stage divider cascade that changes the 32.768 kHz signal to a 1 Hz pulse, and a remarkably tiny H-bridge for running the stepper. We found that last section particularly lovely, and always enjoy seeing the structures traced out. There are even some great tips about using GIMP for image processing. Check out the video after the break.
For those not into the anatomy and physiology of semiconductors, getting a look at the inside of the chip can reveal valuable information needed to reverse engineer a device, or it can just scratch the itch of curiosity. Lapping (the gentle grinding away of material) is one way to see the layers that make up the silicon die that lies beneath the epoxy. Hard drives designed to spin at 7200 rpm or more hardly seem a suitable spinning surface for a gentle lapping, but [electronupdate] just wanted the platter for its ultra-smooth, ultra-flat surface.
He removed the heads and replaced the original motor with a gear motor and controller to spin the platter at less than 5 rpm. A small holder for the decapped die was fashioned, and pinched between the platter hub and an idler. It gently rotates the die against the abrasive-covered platter as it slowly revolves. But the die wasn’t abrading evenly. He tried a number of different fixtures for the die, but never got to the degree of precision needed to see through the die layer by layer. We wonder if the weight of the die fixture is deflecting the platter a bit?
Failure is a great way to learn, if you can actually figure out where you went wrong. We look to the Hackaday community for some insight. Check out the video below and sound off in the comments if you’ve got any ideas.
When you think of machine tooling, what comes to mind might be an endmill made of tungsten carbide or a punch and die made of high-speed steel. But surely there’s no room in the machine tool world for 3D-printed plastic tools, especially for the demanding needs of punching parts from sheet metal.
As it turns out, it is possible to make a 3D-printed punch and die set that will stand up to repeated use in a press brake. [Phil Vickery] decided to push the tooling envelope to test this, and came away pleasantly surprised by the results. In fairness, the die he used ended up being more of a composite between the carbon-fiber nylon filament and some embedded metal to reinforce stress points in the die block. It looks like the punch is just plastic, though, and both were printed on a Markforged Mark 2, a printer specifically designed for high-strength parts. The punch and die set were strong enough to form 14-gauge sheet steel in a press brake, which is pretty impressive. The tool wasn’t used to cut the metal; the blanks were precut with a laser before heading to the press. But still, having any 3D-printed tool stand up to metal opens up possibilities for rapid prototyping and short production runs.
Never underestimate the power of an incompressible fluid at high pressure. Properly constrained and with a full understanding of the forces involved, hydraulic pressure can be harnessed to do some interesting things in the home shop, like hydroforming stainless steel into custom motorcycle parts.
From the look of [Clarence Elias]’s video below, it seems like he has a 100% custom motorcycle build going on in his shop. That means making every part, including the reflectors for the lights. While he certainly could have used a traditional approach, like beating sheet stainless with a planishing hammer or subjecting it to the dreaded English wheel, [Clarence] built a simple yet sturdy hydroforming die for the job. A thick steel ring clamps the sheet stainless to a basal platen with an inlet from the forming fluid, which is ordinary grease. [Clarence] goes through the math and the numbers are impressive — a 1,500-psi grease gun can be mighty persuasive under such circumstances. The result is a perfectly formed dish with no tool marks, in need of only a little polishing to be put into service.
Between manufacturing technologies like 3D-printing, CNC routers, lost-whatever metal casting, and laser and plasma cutters, professional quality parts are making their way into even the most modest of DIY projects. But stamping has largely eluded the home-gamer, what with the need for an enormous hydraulic press and massive machined dies. There’s more than one way to stamp parts, though, and the budget-conscious shop might want to check out this low-end hydroforming method for turning sheet metal into quality parts.
If hydroforming sounds familiar, it might be because we covered [Colin Furze]’s attempt, which used a cheap pressure washer to inflate sheet metal bubbles with high-pressure water. The video below shows a hydroformer that [Rainbow Aviation] uses (with considerably less screaming) to make stamped aluminum parts for home-brew aircraft. The kicker with this build is that there is no fluid — at least not until the 40,000-pound hydraulic press semi-liquifies the thick neoprene rubber pad placed over the sheet metal blank and die. The pressure squeezes the metal into and around the die, forming some pretty complex shapes in a single operation. We especially like the pro-tip of using Corian solid-surface countertop material offcuts to make the dies, since they’re available for a pittance from cabinet fabricators.
It’s always a treat to see hacks from the home-brew aviation world. They always seem to have plenty of tricks and tips to share, like this pressure-formed light cowling we saw a while back.