I have had an interest in metallurgy for quite some time now. I have also had an interest in history for as long as I can remember with feudal Europe as my primary interest.
I hope I can help answering this broad question by being a bit more specific. 1: What made the blacksmith decide what to make? For example: Did the lord give him an order or did he made what the citizens or villagers in his surrounding had demand for?
2: How did the blacksmith acquire ore and fuel? Did he buy it on the market, or from villagers finding ores in the forest or at river beds? Did he go out to find them himself or let his family find it?
3: How did the selling take place? Would he have a stall at a market or would he have a stall right outside the smithy where people would come by and buy something? Or would the customers come by, made an order for example: "Fix these horseshoes." and come by when the order was completed?
4: What kind of forge would be used most frequently during this period? Were different forges used for different goals?
5: Was there a big range from poor to prosperous blacksmiths during this period? If so what kind of blacksmith was expected to be more prosperous?
I hope these 5 guide lines helps you answering. I appreciate the help. I should note that in this example I assumed my blacksmith is a man. I'd rather not add /her /she everywhere. Thank you for reading!
Hi there -- this is not in any way meant to discourage further answers, but here are some previous, related threads you may be interested in. Since some of these are now old/locked, feel free to ping a user here by mentioning their username if you have questions (like so: "hey /u/jschooltiger can you tell me more about ...")
https://www.reddit.com/r/AskHistorians/comments/3cwp3m/we_all_know_that_medieval_and_renaissance/
I hope that you may get an answer that fully satisfies your curiosity - certainly, one of the links you have already received contains good information on the nuts-and-bolts of working with iron - but I feel I ought to warn you that the more social aspects of your question may not be answerable. Indeed, I have been trying to find this sort of information (specifically pertaining to arms and armor production in the 12th century) for some time with no success. What sources we do have from the 12th century are almost exclusively focused on the aristocracy and clergy. As far as I know, there are none that concern themselves purely or even tangentially with blacksmiths. It's rather a black hole as far as many aspects of day-to-day life go. As the author of this link states, the first reference to a medieval blacksmith by name only occurs in 1232. Now, beginning in the 14th century, and especially in the 15th century, we get quite some information on armorers, especially in northern Italy. If you're interested in that, I'm sure /u/WAritter can enlighten you to your heart's content.
I can't speak to the 12th century, since it it significantly before my area of study and, as u/Rittermeister says, before our best records. If you are interested in armourers/weaponsmiths in the 14th through the 16th century, please see this previous answer.