LeMarechal Posted February 21, 2019 Share Posted February 21, 2019 Hello Everyone, this is surely on of the absolute basically questions. And you can trust me, I´ve tried to red all about coal forges hat I was possible to find out there. But for this single question I couldn´t find an answer. Let´s imagin that the fire in forge is started well. My forge has an electrical blower and the firepot gots a throttle to adjust the airflow - the breath of the fire No the question: If I heated up my stock to working temperature and move it to the anvil to work on this piece, what should I do with the airstream throttle while I´m working on the anvil? Should I close it in meaning cut of the airblast and until I put the stock back in the fire, and then open the throttel again? Should I close it only a little bit until I´m back from the anvil? Or should I adjust the throttle to a point of balance (between the airintake and the temperature I want to have in my fire) and after that adjustment, the thottle should stay at this point the whole time I´m smithing? You see it is realy a beginners question, but it is one that unsettles me since years ... Are there any rules or recommdations that anyone like to post here? Thanks Sascha PS.: Don´t wonder if my English is awkward... this old german english Quote Link to comment Share on other sites More sharing options...
Glenn Posted February 21, 2019 Share Posted February 21, 2019 Which solid fuel are you using? Good bituminous coal, junk bituminous coal, anthracite coal, charcoal, wood, corn kernels, etc. How quickly do you work at the anvil? Do you have extra fuel that you can waste? What type product are you making, a garden gate and lots of scrolls, or points on tent stakes? It makes a difference in how you manage the fire. Quote Link to comment Share on other sites More sharing options...
Kevin Olson Posted February 21, 2019 Share Posted February 21, 2019 Every project determines how to manage your fire. If its small and quickly reheated I shut the air off to conserve coal. If its a big piece I leave the air going some to keep the fire as hot as possible and just keep feeding it coal. Because I don't like to stand around waiting for the forge to come back to the screaming hot fire the piece needs . But in the end only you can determine how to manage your fire. It takes time at the forge to figure this out. I hope this helps. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted February 21, 2019 Share Posted February 21, 2019 With good bituminous coal and an electric blower and reasonable amounts of time at the anvil and working only 1 or 2 pieces at a time and only me working in the forge and not forge welding I like the fire to coast when I'm not there. *Especially* when doing demos! Saves fuel and steel, less scaling generally too. Notice how many qualifiers were in that sentence? For people starting; out a foot switch to control the blower that requires constant pressure for "on" can be very nice indeed. More advanced smiths may like a switch that you click on/off. And when you get into production work, you may do very well with a constant air supply and match it to the size and number of workpieces in the fire. About 20+ years ago I did a demo for a smith at the Fränkisches Freilandmuseum Bad Windsheim on welding up a billet. (Why yes I did bring a billet and borax for pattern welding on an international business trip, 90 days, I knew I would have to find a forge or go crazy!) Where in Germany are you at? Quote Link to comment Share on other sites More sharing options...
LeMarechal Posted February 21, 2019 Author Share Posted February 21, 2019 Ok that all helps very very much.And it calms me down to see, that there is indeed not that one answer to that question. Calms down because sometimes I thoght "I´m too stupid to look for" Some of these thoughts you wrote above came to me, but to hear that from other and much more experienced people makes me more confident on my own way. The last week I made very much tongs. And for this, I found it well working with that constant air supply. But if I do some tricky and frickling things, like trying out something new, constant air makes now sense I thoght. I´m happy to see that I wasn´t too wrong with that. One thing I have to work on, by stopping the airblast or reducing the airflow, is to remain myself cool while the fire heats up again (hope this pun works ) Meaning that I often become very impatient during waiting for the forge reheating. That leads me to overdo the air supply, resulting in to much scale, to much heat and so on... @Thomas I´m from Hamburg... completely other direction Far far away Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted February 21, 2019 Share Posted February 21, 2019 5 hours and 47 minutes, that's almost next door here! There is a highway sign I go by regularly on I-10 in Texas that says: Beaumont TX 862 miles...and they are both in the same state... Quote Link to comment Share on other sites More sharing options...
LeMarechal Posted February 21, 2019 Author Share Posted February 21, 2019 a 5 hours yourney here stands for an adventure that requires a lot of planning and prearrangments. You know, you have to take the car to the service station, to be sure that it will survive such a long trip. You have to bring yourself to the doctor to get all possible vaccinations (cholera, yellow fever etc). The insurance man has to update your life insureance.... Make a will... Get enough food for the trip, not least - enough water etc etc etc... You see, things are a little little bit different here - - :) Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted February 21, 2019 Share Posted February 21, 2019 Things must have gone down hill since I had to drive from Frankfurt AM to Leipzig a lot.... Quote Link to comment Share on other sites More sharing options...
LeMarechal Posted February 22, 2019 Author Share Posted February 22, 2019 Quote Link to comment Share on other sites More sharing options...
JHCC Posted February 22, 2019 Share Posted February 22, 2019 As noted above, much depends on the fuel. Forge fires of bituminous coal, charcoal, wood, and corn generally are able to sustain themselves without a constant supply of air, so you have a choice. Anthracite, on the other hand, Will Go Out if it doesn't have a steady stream of air at all times. My own forge setup has an electric blower on a variable transformer (variac) that adjusts the speed. If I'm burning anthracite, that's all I need. If I'm burning bituminous (especially on smaller jobs, as Kevin Olson notes above), I'll add a "deadman" switch to the electric supply to the blower, so that it only runs in I'm standing on the pedal. As ThomasPowers says, it saves a lot of fuel to only run the fire when you have to. Quote Link to comment Share on other sites More sharing options...
Glenn Posted February 22, 2019 Share Posted February 22, 2019 The specifics on my forge are that the blower and air pipe to the forge are NOT connected to each other. If you want more air, aim it more directly toward the air pipe, for less air, aim it less directly to ward the air pipe. After a while you find there are maybe 3 positions that you use most often so visually take note as to there they are. Once a good fire is established that you like to work with, mark the blower to pipe angle position .This is the constant air flow you use for your forge at the heat you like to work with (working position). When you step away to the anvil back the air flow off to where you maintain a good but not so aggressive fireball. (idle position) When the metal returns to be heated up a bit, add more air to your working air position. There is a small amount of lag time involved bringing the fire ball up to heat but not much. As the fuel burns it will need to be replaced with coke from the edges of the fire. Collapse any hollows or holes and back to work. Phase two is much the same except that you are doing a lot of smaller stuff and need a piece of metal to always be hot. This is where you find the working heat and go just bit above that temperature in the fireball, but still below the temp the metal starts to burn. Work with the fire and run it at that constant temperature. Put one piece of metal in the fire ball, one on each side of the fireball, and two or three pieces laid on top of the fire to preheat. The piece of metal comes out of the fireball as one from the side is placed from the side into the fireball. Next round, one piece of metal comes out of the fireball as two pieces of metal are placed onto the side of the fireball, and two more pieces of metal are placed on top of the fire to preheat. It is a dance for sure Warning, this method will wear you out as there is always a piece of metal ready for the anvil with no rest or down time for the smith. You forge in your location with your fuel can be adjusted to do much the same thing. Just takes practice. Quote Link to comment Share on other sites More sharing options...
LeMarechal Posted February 23, 2019 Author Share Posted February 23, 2019 I will try to get some photos of my forge today. Glenn, that were exactly this points I would like to get more information about. Thank you very much. If I came to other blacksmiths or some demonstrations I tried to catch skills about how to manage a fire in real life. But on hammerins it is a little confusing to see how the others work their fire because, like Thomas explained above, for demonstrations you need an other kind of firemanagment than at home, if you're alone. On the other hand it must be said, that you can see some very absurd things on meetings. Once I met an experienced smith and he had a forge with a very flat firepot and nearly no coal in it, supplied with far to much air, he called this a "nice"sharp and fast fire. Everything he was working on during his demonstration burned and he got excessive scale... but he was happy with that- I was very irritated after that meeting Quote Link to comment Share on other sites More sharing options...
Glenn Posted February 23, 2019 Share Posted February 23, 2019 When producing many pieces quickly you will burn more fuel to keep the fire very hot at all times. With a little practice you can make things look smooth and not expose the details of what is happening. With two people working, one on the anvil and one on the fire, you can produce an amazing amount of product. You only do one step or operation at a time, and by doing one step several times you naturally speed up the process. Take the S hook for example. Cut the stock to double the length needed. With that length you do not need tongs. Put a pig tail and loop on one end and set it aside. When all have one pig tale and loop, cool the entire batch and put a pig tail and loop on the other end of all pieces. Now heat the center and cut the length in half. While the piece you are holding is still hot, put a pig tail and loop on the cut end to finish one S hook. Cool the pile of half completed parts. Now heat the end and put a pig tail and hook on each. You will see pig tails in your sleep at this point. The sequence makes sure you do not have a hot end to deal with at any time. No mistakes, no burns. The same technique can be applied to other pieces in a production process. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted February 24, 2019 Share Posted February 24, 2019 And note: When you cut them in two, don't cut straight across the piece; cut at a sharp angle thus starting the ends of the other tapers. I had a student once making a bunch of tent stakes out of 1/2" sq scrap. Not much profit margin in a tentstake especially as he was cutting across and then tapering to a point. He saved a lot of time, fuel and arm after I told him about cutting on the angle. Quote Link to comment Share on other sites More sharing options...
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