71 and building my first foundry oven. At this point I am actually still acquiring the needed items for my melting furnace. As I only need to melt aluminum and some copper for alloying aluminum-bronze for now I am going cast-able cement and perlite with a 1 to 2 inch kaowool backing. If I decide down the road that I need to cast iron I will more than likely just build an upgraded iron melter. Anyway a little about me. I have a roughly 30 x 70 pole barn machine shop. Am not a machinist but do enjoy my mill and lathe. Like a couple of other people my goal for now is casting milling and turning stock. Spent 35 years as a self employed silver and goldsmith so am not completely new to melting and casting but that was mostly lost wax casting as well as some sand casting and cuttlebone. I have been lurking for a couple of months and decided to join.
Welcome. You’re in good company here. Depending on the castable you choose (along with the koawool), you could skip the perlite and build an iron capable furnace right from the get-go even if you don’t go high-temp right away. You know how it is when you start getting down to it: “If only my lathe was an inch bigger; if only my door was 2 inches wider” etc, etc. I started with an 8” bore and needed a 10” almost right away! Lol. Pete
Petee716. This setup is going to be propane fired and as I am on a fairly limited budget I was concerned with slow heat up times meaning more propane used, as well as the fact that for right now I am only going to be doing aluminum and a bit of aluminum-bronze. I had considered it in the beginning but opted hopefully for less propane consumption.
Hi, welcome to the forum. You can line a kaowool furnace really cheap and easy by painting on a few layers of satanite refractory mortar and firing it between coats. Better still, it's incredibly fast to heat up due to the minimal thermal mass of the 1/4" thick (or less) hot face that is built up this way. My propane furnace only needed a 5 pound box of satanite to coat the whole interior (build thread is linked below in my signature if you want to have a look). I have some extra left over for patching cracks, but 2 years along and so far I haven't had to. The rim of the vent hole in the lid might get a couple dabs soon where it's been knocked by tongs and ingots a bit though. Whatever you build, make sure to take and post pictures! Jeff
Nice to read that you do gold- and silversmithing. That is my hobby as well. I don't do muh now, but recently I made a silver photo frame. I learned melting and casting also for making silver / gold sheet and wire myself as it is much cheaper. And when I spoil a workpiece I discard it and remelt the metal to make new material.
Metallab: The metals and everything else about making it just got to expensive. When I started smithing an ounce of silver was around $5.00. I however could not have picked a better occupation for what I learned. Metals alloying for sterling silver, all karats of gold as well as colored golds, gem cutting both cabachon and faceted stones and on and on.
Welcome Old Timer! Lots of great info and great people here to teach the tricks. Like Tobo there....Full of awesome tips.
