This video shows how ductile iron is made on a small scale, have a look at 13:39 where they use a teapot ladle with a lid to contain the vigorous reaction when magnesium boils. They were casting a crankshaft. Ductile iron should be doable in a backyard setting.
I don't know about anything about ductile iron production so I won't comment on that aspect of the video but I did notice a few other interesting things. First, what are they using for insulation on the lid of the melting furnace that the guy is able to sit down on it a foot and half from the opening? Next, I found they way they used the extended riser interesting, filling the mold through the sprue, blocking it off with sand then topping off the riser with more iron, in effect, the riser is its own hot topper. Finally, that's a Scat flat plane V8 crank, a comparatively high performance part. Scat is an American company best known for its performance air-cooled VW parts, head office in Redondo Beach California.
I did see them throwing on a coagulant material on top of the melt which I assume is unexpanded perlite a couple of time in the video 1:16, 14:04, 14:19 and 14:32. Rocco, that furnace is an electric induction unit, you can see when it tilts there's a lot of space under the platform so the heat would be a lot less on top than a fuel fired furnace.
Yeah, it was a bit surprising that they don’t just elevate the sprue to begin with. Maybe it’s to minimize erosion at the bottom of the sprue. The riser is certainly massive enough to remain molten during the operation. I’m sure there was trial and error involved to get the balance of temperature and timing such that merely patting sand over the sprue was enough to keep the metal from pushing back out. Pete
Looks like a Western foundry in the 1920s. No safety gear, all unprotected eyes and faces and bare feet ... I wonder how many accidents happen there.
If you get low sulphur scrap or ductile scrap as a base melt it is completely doable. CGI is probably as good as most would need at home, so even if you dont wind up with the right amount of nodularity to hit premium ductile you will almost certainly hit CGI with the right amount of additions.
Even more than the accidents, I wonder what these guys lung x-rays look like? Average life expectancy?