Scientists found a surprising amount of lead in a glacier. They were studying atmospheric pollution by sampling ice cores taken from Alpine glaciers. The surprising part is that they found more lead in strata from the late 13th century than they had in those deposited at the height of the Industrial Revolution. Surely mediaeval times were supposed to be more about knights in shining armour than dark satanic mills, what on earth was going on? Why was the lead industry in overdrive in an age when a wooden water wheel represented high technology?
The answer lies in the lead smelting methods used a thousand miles away from that glacier, and in the martyrdom of a mediaeval saint.
Continue reading “How Can Heavy Metal Fly?”
When I went to a hacker camp in the Netherlands in February I was expecting to spend a few days in a comfortable venue with a bunch of friends, drink some beer, see a chiptune gig, and say “Ooh!” a lot at the exciting projects people brought along. I did all of those things, but I also opened the door to something unexpected. The folks from RevSpace in the Hague brought along their portable forge, and before long I found myself working a piece of hot rebar while wearing comically unsuitable clothing. One thing led to another, and I received an invite to come along and see another metalworking project of theirs: to go form ore to ornamental technology all in one weekend.
From Dirt To Space is a collaboration between Dutch hackerspaces with a simple aim: to take iron ore and process it into a component that will be launched into space. The full project is to be attempted at the German CCCamp hacker camp in August, but to test the equipment and techniques a trial run was required. Thus I found myself in a Le Shuttle car transporter train in the Channel Tunnel, headed for the Hack42 hackerspace in Arnhem where all the parties involved would convene.
Continue reading “From Dirt To Space, Backyard Iron Smelting Hackerspace Style”
Microwave ovens are a treasure trove of useful parts: transformers, an HV capacitor, a piezo speaker, and a high torque motor, to name just a few. In a new twist, [Rulof Maker] strips all that out and uses just the metal case to make a furnace for melting aluminum, copper and bronze.
His heat source is a quartet of 110 volt, 450 watt quartz heating elements which he mounts inside in the back. To reduce heat loss, he lines the walls with ceramic fiber insulation. Unfortunately, that includes covering the inside of the window, so there’s no pressing your nose against the glass while you watch the aluminum pieces turn to liquid. If you’re going to try making one of these yourself then you may want to consider adding a fuse.
It does the job though. In around nine minutes he melts enough scrap aluminum in a stainless steel bowl to pour into a mold for a test piece. But don’t take our word for it, see for yourself in the video below.
If want more information on what useful parts are inside then check out this primer. Or you can leave the parts in and use the oven as is for melting lead, but keep a fire extinguisher handy.
Continue reading “A Different Use For Microwave Oven: Melting Aluminum”
[Th3BadWolf] decided to undertake a casting foundry project of epic proportions. The hardest part of the build is obviously the apparatus for melting the metal. It needs a vessel that can stand up to the heat, and a heating method that has enough thermal power to melt metal. He’s just finished the burner portion of the build. His writeup includes information about the cement casting that finishes up the vessel on which he had already done a lot of work.
You’ll remember that for the enclosure he started with an oil drum and lined it with a ceramic blanket. That was lined with fire brick. In this update he finish it off by placing a smaller barrel inside to act as an inner form, then filled the remaining gap with 3000 degree cement.
The burner injects air, propane, and oil which are all driven by a blower and forced through a nozzle into the chamber. You can catch a quick blower and burner test clip after the break. We can’t wait to see the next post, which we assume will be a test run of the final assembly.
Continue reading “Two-thirds Of A Casting Foundry”
[th3BadWolf] has been wanting to build a foundry for some time now. Done right, it’s a very neat tool; it’s fairly easy to do aluminum castings, and if you’re clever enough a foundry can lead to building large machine tools such as a lathe or a mill. Anything worth doing is worth overdoing, so [BadWolf] is designing his foundry to melt 150 pounds of aluminum every 45 minutes.
The build began with a humble oil barrel. [th3BadWolf] cut the top off of the barrel and began lining the inside of the barrel with a ceramic blanket and refractory bricks. To hold this somewhat precarious assemblage of blanket and brick together, [BadWolf] is holding everything together with 3000° F cement.
The body of the furnace is nearly complete, but [BadWolf] still has to drill a few holes for the burner system. He’s going to start each burn with Propane, then move over to engine oil when the furnace gets hot enough. Truly an awesome project, and we can’t wait to see the results.
Here’s one good thing about the bitter cold Midwestern winter, it helps keep you from overheating when working around a hot furnace. Back in February this iron pour happened in the parking lot of the Madison, Wisconsin based Sector67 Hackerspace. Look, they’re making iron hearts!
Now this isn’t just a bunch of members who got together and decided to do some casting. As you can tell in the video after the break the team knows what they’re doing. The event was a collaboration with FeLion Studios, a custom cast-iron art boutique. But the Hackerspace participants did get to take part in the process of building the cast, watching the pour, and cleaning up the rough results.
One of the people from FeLion Studios just appeared on the Martha Stuart Show, along with a 550 pound cast-iron frying pan United States map. [Chris] from Sector67 tells us the New York frying pan that [Martha] is hold was a product of the parking lot pour.
Continue reading “Iron Casting In The Parking Lot”
If you’ve ever wanted to forge, cast, or smelt metal, this project is right up your alley. It’s a 30 kVA induction heater built by [bwang] over on Instructables. It gets hot enough to melt and forge steel, iron, and aluminum.
An induction heater operates by surrounding the object to be heated with a coil carrying high frequency AC current. Basically, the entire setup acts like a huge transformer with a shorted secondary. To get these currents into a workpiece, [bwang] used a TL494 PWM controller as an oscillator. The output of the TL494 is filtered and amplified a few times to generate a huge amount of AC current.
Larger versions of [bwang]’s induction heater are found in foundries and forges all across the land; even though this small version sucks down 50 A out of a dryer or stove outlet, induction heating is very efficient. We’re actually wondering why we don’t see many home blacksmiths using induction heating, so we’ll leave that for our readers to discuss in the comments.
[sessions] reminded us of this induction heater from a few years ago. A little smaller, but still usable.