Hi all, I have been reading in this site nearly every day for 8 weeks now! I have learned a tremendous amount and am essentially on information overload. All that being said, I am planning a furnace build. I always thought that I never did anything small ... until I read MarCaap's build thread! Well my furnace will not be that big or elaborate, 30gal drum more on the lines of Mjonkman's and Tobho Mott's.
I really want/need to pour iron (I know, I know, at some point) and want to build a furnace to take me there. At max I can see a B10 or B12 crucible, not sure if I will get there ... but want the ability to go that large. I have a lathe, milling machine, etc, so I could end up like myford boy (I wish!) and I also repair old farm windmills, thus the want/need to pour iron.
Anyway, enough babbling. Here are my current thoughts on dimensions etc:
- 11.25"d x 14.25"h interior with 1.25" hot face.
- Hot face probably from Sparcast LC 32 AL (rated for 3200*F, but still waiting for info from another supplier).
- Hot face wrapped with 2" of ceramic wool.
- 3" high plinth.
- 3" top clearance on a B12.
- Lid similar to the sides ... HF and wool.
Now for my questions:
- What should I back/support the bottom hot face with? I was thinking IFB, then saw some comments that talked about not enough support. So what about dense firebrick? Any other suggestions? My thought was to pour the bottom in place like Tobho Mott did.
- SS needles or not in the hot face, lid, bottom? I have read yes, no, maybe on different aged threads ... what are current thoughts.
- How much will a 2" layer of ceramic wool "fluff up"? Rough measurements, I will have .5" of diameter unaccounted for (to the barrel diam). Will a 2" layer of wool expand an extra .25" all the way around?
Let me know your thoughts and opinions. This will not be a fast build, but I will be sure to post pics (I see you guys like them). :-)
Thank - Ed