Some of my early memories are of exploring my grandfathers workshop in Colorado Springs, CO. They had a Craftsman style home with a nice deck out front and huge trees in the back inhabited by opinionated squirrels. In the corner of the basement, near the sprawling octopus furnace (used to be coal-fired, straight out of a scary-movie), his tiny workshop existed: It was a magical place where sunlight crept in the single small window illuminating dust motes settling on a variety of magical items (for a young grade-schooler): Transparent models of V8-engines, drill-presses, lathes, wood-working tools, and all the amazing things Grandfather had created, many of which were aluminum cast in sand. One of the coolest was a cast-aluminum ‘bear-paw’ gas pedal. Those memories have stuck with me to this day, and for the longest time I’ve had the urge to melt and cast metal. Today I made the first steps to making that happen.
People ask me what my goal is with this: A few months back I picked up a Makerbot Replicator. I’ve been having issue with it, and will have a proper post when it’s all sorted out (hopefully very soon). Conceptually, I want to make generative volumetric art via Processing or Python, print it via the Replicator, and then cast it in aluminum\bronze. I know how to 3d print, I know how to program, but I don’t know how to melt metal. Well, as of today I do.
Researching the subject I picked up the book “The Flowerpot Crucible Furnace” by Lionel Oliver II, and it was the perfect introduction I was looking for. It walks you through the steps from creating a furnace out of a flowerpot (and a few other ingredients) to melting aluminum in it. I actually made the furnace last year, but wasn’t until the stars aligned today I was actually able to melt metal in my backyard.
Enough words, time for pics and vids!
Here is the initial setup:
From bottom to top: Hair-drier (blower), steel tube connecting blower to furnace, crucible (loaded with aluminum chunks), flowerpot furnace, crucible tongs, dross\slag (junk that sits on top of melted aluminum) bucket, furnace lid, cupcake tin (for making ingots).
Here’s a shot of the crucible (filled with chunks of aluminum) in the furnace, surrounded by charcoal (already lit in the bottom):
In this video, I’ve put the lid on, and turned on the blower for the first time. When I put my shadow over the exhaust hole you can see it glowing red already:
In this video, I ‘reload’ the crucible by removing the top of the furnace, re-seat the crucible, and add aluminum. You’ll see a piece of metal sticking out of the crucible that hasn’t yet melted. There’s a reason for that… In the process I drop a briquette into the crucible, and remove it with a spoon. I found it interesting that no aluminum stuck to the briquette:
In this video, I pour the aluminum into the cupcake pan. You’ll notice the long piece of metal is no longer present. It didn’t melt: It was steel It was removed.
Here’s a shot of the final product, with the ingots on the left:
And a shot of me with my new cupcakes
So what is next? I need to build a sand-casting table so I can start the process of actually doing something with this metal. In the meantimes I’ll be enjoying my cupcakes.
Big thanks to my father for both providing me a bunch of scrap aluminum, and fabricating the crucible