First AL cast - a sort-of success! The part - a simple bottle opener off of thingiverse, that would probably only last a few brews even if printed in poly-carbonate The result - a somewhat ugly part that looks a bit better after some cleanup. Reasons it didn’t come out perfect - the plaster of paris I mixed with the playground sand for the mold was actually joint compound, and so had a certain amount of latex in it. Additionally, I didn’t take the time to blow out the mold after burning it out. The mold itself was done in a bit dodgy way in any case. Still, as you can see the layer lines and top/bottom surface finish, I’m encouraged by the result!
And, as it’s opened at least 6 beers, and hung a large metal chair from the opening tab, strength is not an issue…
Great first attempt, sounds as if your next casting will be even better.
It opens a beer what else can you ask for - success.
I really really want to try this. need to make a crucible I guess. (and a furnace)
I used a small paint can as a crucible, worked great. You want something with thin walls, the length of 2" steel pipe with an end cap I tried I couldn’t get enough heat into
- the walls need to glow red hot!
You’re going to probably be annoyed slightly at me saying this, but that attire is not safe attire. Please be very careful. At the very least wear pants and leather boots next time.
That… Is… Freekin… Awesome!
@ThantiK Your absolutely right that the shorts were an unsafe idea - but that picture is actually from an early firing, where I was just creating some ingots. It’s a lame excuse, but I did wear pants and boots when I did the large pour into the mold a few days later. I’ve read up on the safety risks, and the largest one seems to be concrete’s tendency to explode if exposed to molten metals (only occurs if it is the slightest bit moist.)
@Heath_Ebert - I did an earlier post on general construction of my furnace, but basically an air mattress blower connected to a conveniently sized length of broken pole vault pole is coupled via aluminum foil to a 2" long, 1.5" length of steel pipe. The pipe goes from the outside of the larger steel bucket, through the quickcrete, and into a standard paint container I bought new (and clean.) I plan to eventually try gas, but for now about 10 charcoal briquets provide ample heat to get the smallest sized paint can crucible glowing red hot. I have been melting aluminum scrap from work, as the # of cans and the crud from their coatings make other sources a pain.
Still need to find some of the good “plaster of paris” for making a mold. Anyone have an idea of a brand name or type that home depot or lowe’s might stock?
Lowes or Home Depot aren’t going to carry plaster of paris; It’s generally a craft-style item. Wal-Mart, Hobby Lobby, etc should carry it. Like this stuff: http://www.walmart.com/ip/Kids-Craft-Plaster-of-Paris-8-lbs/19526542
You know, I just threw out one of those air mattress blowers because I assumed the duty cycle was crap. I held it my hand and said “I’m sure I can use this for something…” 
@Chet_Wyatt - the thing does get pretty hot during an extended run, and will likely wear out, but as I don’t plan to use charcoal forever I haven’t worried about it. They are designed to run for at least 5 or 10 minutes against a gradually increasing pressure gradient I’d imagine. And thanks for the tip @ThantiK !
Hi, with a couple of hundreds dollars you can have a last technology very clean electrical induction heater home/hobby mini melting furnace. They are extremely quick in melting.
They exist in various shapes and prices. here is one chosen randomly:
http://www.aliexpress.com/item/220v-2kg-gold-copper-silver-aluminum-iron-steel-induction-melting-furnace/733476264.html
Very clean, sure. Expensive as heck; yeah. Honestly LP gas is probably much better. Cheapest is coal, but the fumes can be neurotoxic.
While induction is clean and awesome sure, I also need a way to burn the PLA out of the molds