Updated: Mar 4, 2020
It's been awhile. Lots going on in Makerneer-land! Let me catch you up a little.
The latest experiment in the laboratory involves casting molten metal. Say that again, molten metal. Yeah, something about liquid metal is just neat and seems to scream "WE'RE DOING SOMETHING DANGEROUS SO IT MUST BE IMPORTANT!!!" Well... at least to me anyway...
OK, so what led us to believe we could liquefy metal and cast it into shapes with simple household tools?!
The internet, of course.
(Yeah, you're right, that is kind of an odd combo of channels... Wonder how often they get mentioned in the same sentence?!)
Right, moving on, we have FIRE to talk about!
AvE used a handheld torch to melt some small chunks of aluminum. I have one of those, but I wanted to try melting aluminum cans first instead of possibly ruining some of my decent aluminum. So... a weed burner is basically a big torch right?
OK, torch, check. What's next? Next we need something to melt the aluminum in. AKA a crucible. Crucible sounds like an expensive calibrated laboratory item, but turns out they're pretty cheap. Following TKOR's advice I found this one on Amazon that will easily fit a whole aluminum can. It did arrive with a couple chips in the rim, but (spoiler alert) it didn't melt or explode when heated red hot, so bonus points.
OK, fire making device, thing that won't melt to put stuff in, next we need something to hold the crucible and something to pour the molten metal into.
Turns out a steel muffin tin can be used to make aluminum ingots. Excellent, we have a few of those that, to my knowledge, haven't been used in years.
However... Wiferneer was not very impressed with my chosen course of action to free up space in the kitchen by re-purposing our muffin tin for "experiments."
Hokay then. Sounds like a trip to the thrift store is in order. Why is it that all good experiments seem to require a trip to the store before they can be completed?!
Thrift store trip was successful. I acquired a mini muffin tin, 2 sets of tongs, a 12v power supply, slate coasters and a wide leather belt. They were out of lampshades...
OK, can we please just melt some stuff already!!!
YES, ON WITH THE SHOW!
Wait, game off, this will be hot. Find the welding gloves.
I started to season the crucible with Borax soap as the instructions recommended (I didn't realize Borax could be used as a flux material), however, the sand I had the crucible on started to "pop" and fly all over the place.
Flying superheated sand... Hmmm. Wasn't really expecting that... guess it makes sense, moisture evaporating, blah, blah, blah... Still. Want. To. Melt. Metal. TODAY!
Using a large rock is probably a bad idea... I could probably get the fire bricks out of the BBQ?
Ah, right. Lets just use the handy dandy chunk of railroad track I'm sure everybody else keeps near their fire pit like I do!
(I can see you're looking at me funny... I've been learning a little about blacksmithing and use it as an anvil)
Apply medium heat and wince...
Perfect, no more exploding superheated sand.
After the borax was melted and seemed to have been absorbed into the crucible I put a can in and gave the crucible full heat. The can collapsed but didn't really seem to "melt." I stuck a few more in and gave it full heat for about 5 minutes.
IS IT MELTING YET?!
Kind of? There's a lot of junk on top.
I put a few more can in and the cans kept disappearing into the hot crucible, so I assumed that it was working. Once a dozen can had disappeared, I stirred the bottom of the crucible.
THERE'S LIQUID ALUMINUM IN THE BOTTOM OF THE CRUCIBLE! SUCCESS!
Huh, cool! That was actually easier than expected. Lets pour!
Pouring was a little tricky. There's a lot of crap (I learned it's call "dross") that floats on the top. My first pour was a little ugly, so I decided to give it another 5 minutes of heat. That seemed to help, either the aluminum was more "liquid" or I'd disturbed the dross enough to make a decent pour path and a actually ended up with some decent looking aluminum muffins! Checkout the pictures below!
Alright. That was fun. But is there a reason other than, because we can, for melting aluminum? (not that that's a bad reason...)
Yep, there is.
3D printers are excellent tools for making unique molds. So, for me sand casting is the next step in learning how to fully utilize my 3D printers. In fact I have a large format 3D printer that I'm setting up right now that will allow me to create models that are over a cubic foot with no seams. This will get interesting! Stay tuned and let me know what you'd make with molten aluminum!