I'm looking at iron longer term, and intend to work with mainly bronze and copper initially. I am also seeking out some instruction locally, though it isn't easy to find. I have a strong interest in blacksmithing in general, and a strong desire to melt down metals and turn them into things. Be they useful, or just artwork, etc. I'm also an avid LARPer, and we can make use of a plethora of iron items.
Yea, I can find 2300-2500 F stuff reasonably easy, which would at least get me as far as the lighter metals. It may be the eventual route I take short term. I am not looking at hardware stores for anything, I've been checking with brick yards and such, unfortunately the more industrial places I have found them have had untenable minimum orders (hundreds or more pieces). High alumina and cordundum-mullite bricks, and a few others fit the needs, it's not a matter of not knowing what I'm looking for so much as sourcing them.
For steel it's really more of a question of whether I'm making steel, or just melting and reforming existing steel. Makes a big difference on how consumable my interior will be. If I can do the temperatures needed for iron, I can do steel if it comes up. It is not my focus.
Type R or S? I'll look into that, the ones I had seen were Type B, but they were either prohibitively expensive, or simply not accessible (MoQs again). The thermocouple is important for controlling the temperature, and keeping it stable. I obviously don't want to run things too hot and damage the coils or the furnace itself.
Maybe I can assuage a bit of your concern with the knowledge that I've spent quite a large number of hours over the past couple of years reading literature on smelting, foundries, forging, and so forth. Also I'm a scientist by trade, safety equipment is the very first consideration in everything.