7 ms·

Took my daughter to check out a blacksmithing class in Brooklyn and was pleasantly surprised to find there was no open fire at all. The iron and steel are heate

by bcks 3y ago

Took my daughter to check out a blacksmithing class in Brooklyn and was pleasantly surprised to find there was no open fire at all. The iron and steel are heated by an induction machine. Just use the tongs to hold up your material near the coil and press the pedal and voila, it soon starts to glow red hot. The space is small, maybe 3 students at a time plus a teacher, but it was bright, tidy, and clean. Not at all the dark, sweaty cave of fire and fumes that I'd imagined, and interesting to see tech slightly more modern than fire.

kibwen 3y ago
That's an incredible application of induction heating that I hadn't considered. How big was the coil?
- bcks 3y ago
  Maybe 6 inch diameter.
  - bcks 3y ago
    Ah, my bad - looking at induction forge images and links in this thread, the coil was probably closer to 3 or 4 inch diameter.
- toomuchtodo 3y ago
  Induction forge. https://youtu.be/P_STrnP__D4 https://youtu.be/P_STrnP__D4
  - latchkey 3y ago
    Kind of wild to watch him hold the rod with his bare hands while it gets red hot.
    - dreamcompiler 3y ago
      Steel is a poor conductor of heat. You cannot do this with aluminum or copper.
      - scoot 3y ago
        You can’t do it with aluminium or copper at all. There will be no heat to conduct, so hold it as long as you like.
        grozzle 3y ago
        A myth. Copper and aluminium won't heat on a consumer-grade kitchen induction stove, which only have a set of coils designed for ferrous metals, but restaurant kitchen professional IH stoves can use the different frequencies that heat non-ferrous metals, and a forge or melting furnace can indeed melt any metal, ferrous or not.
        derbOac 3y ago
        Why don't residential induction stoves have that capacity? Given the popularity of aluminum and copper cookware I'd think it would be pushed out. It's one thing people always bring up with induction ranges.
        grozzle 3y ago
        The electronics to drive the right frequency for efficiently heating ferrous metals (about 25KHz) are affordable. The electronics to drive the much higher (at least double?) frequencies for non-ferrous metals safely are not so affordable. It would add more to the cost than a new set of cookware. Cast iron is the king of cookware and works great on IH, anyway! You can put a few mm thick piece of steel on top of the hob and then set your copper pan on that, as a workaround.
        japanuspus 3y ago
        This is incorrect. The magnetic flux will induce an electromotive force that will cause a current to flow in any conducting material and cause heating if this material is not superconducting. As an example, induction heating is a commonly used method in zone melting for Si-purification [0]. The effect is more pronounced in ferromagnetic materials because a larger flux is induced. [0]: https://en.wikipedia.org/wiki/Zone_melting https://en.wikipedia.org/wiki/Zone_melting
- hef19898 3y ago
  You can even do induction hardening. Used for complex parts, of if you want hardening with a very well defined penetration depth. The place I used to go had a gas furnace to heat the metal. A pitty I didn't find time to go there for ages now... Only downside of gas furnace, closed on on end, is the limited length of the stuff you can put in. I have an idea I want to try to forge longer things, but again, it is months now I didn't have time to get back to it...
  - hacknewslogin 3y ago
    You just have to put a door on the back of the forge. Or block the back opening with a firebrick.
    - hef19898 3y ago
      Yeah, but it is not mine! Also, there is a open gas forge sitting right next to it. So, the place decided if some work and investment is done, it will be on the open forge. Which I can only support! But yeah, I just realized the last time I was there was last year before christmas... Good thing anout this is: the day I retire I will definitely not be bored at all!
1letterunixname 3y ago
Cookie-dough coffee can forge*: https://youtu.be/FmEb1YZScxc https://youtu.be/FmEb1YZScxc DIY induction heater**: https://youtu.be/wKFnk4R54ZQ https://youtu.be/wKFnk4R54ZQ * Unsafe because it depends on combustion and creates nanofines/ultrafines ** Unsafe because there's no current limiting, no temperature limiting, no grounding, and no crucible confinement
- mkii 3y ago
  I'm hesitant to get into physical project hobbies (e.g. low-voltage electronics, wood-working, 3D printing) because I'm afraid of all the hazards that I don't know about. Seeing these warnings (while greatly appreciated in a theoretical sense for me) just reinforces this fear I have.
  - grogenaut 3y ago
    "the state of california is known to the state of california to cause cancer" - placard on jetway on way into california from origins unknown. You can't know every risk. You can be paralyzed by fear and never grow. Life is a calculated risk. Do dirty things in a seperate space from your living. Wear PPE. As others have said the risks for hobbies and work are different. Hell we may all be having mesothelioma from the atmosphere in 30 years. And sitting at indoor hobbies will also kill you from heart disease etc. You are not getting out of here alive.
  - debacle 3y ago
    Start in a classroom setting. Check your local community education classes.
  - mauvehaus 3y ago
    Do woodworking. The whirling blades are pretty apparent. Wear a dust mask while sanding, and take comfort that Jesus was a carpenter and didn't die of respiratory illness/failure. Don't do your own rigging or wiring, and you'll probably be fine. I do much of my own on both and I'm still ok. Watch the tommy bar on your vise, and mind your marking knife. The apparently harmless things will get you because you pay them less mind. Source: am a furniture maker. I still have 10 fingers. Haven't died of respiratory illness yet. Nor have I burned my shit down or crushed myself moving machinery. I have definitely made an unplanned trip for super glue after slicing myself with a marking knife.
ExoticPearTree 3y ago
But is it really blacksmithing if you're using real fire? I mean that's the idea, to heat metal in an open fire and then hammer it, rinse and repeat.
- eesmith 3y ago
  The idea is to heat metal until it can be shaped more easily, traditionally by hand tools. That does not require a fire. In Roman mythology, the blacksmith Hephaestus used a volcano as his forge. Traditionally it required a fire, yes, but that doesn't make it essential. I use silverware which is not made of silverware. As a point of definition, in general use, a forge is not an "open fire". Eg, https://idioms.thefreedictionary.com/open+fire https://idioms.thefreedictionary.com/open+fire defines "open fire" as "A fire not contained by a fireplace or stove" and https://dictionary.cambridge.org/us/dictionary/english/open-fire https://dictionary.cambridge.org/us/dictionary/english/open-... defines it as "a fire that you light outside, for example to cook on, or a fire in a space in a wall of a building, with a chimney to take the smoke away". As I understand it, blacksmithing is typically not done outside, where it can be too bright to use the color of the metal to judge the temperature, and the fire in the forge requires some sort of forced air (eg, a foot-powered bellows forcing air through a tuyere into a constrained fire). This means the forge is not an open fire. TIL blacksmithing has its own definition for "open fire", which is distinct from "stock fire". See http://www.faadooengineers.com/online-study/post/first-year/basic-manufacturing-process/679/open-fire-and-stock-fire-furnace http://www.faadooengineers.com/online-study/post/first-year/... . This means a blacksmith wouldn't say they only use an open fire.
  - ExoticPearTree 3y ago
    My point was that heating metal over open fire and using tools to keep the fire going is what gives it that medieval allure and makes it to be a bad ass hobby.
    - eesmith 3y ago
      My point is that "open fire" is the wrong phrase. Just say "over a fire." Medieval blacksmiths did not use an open fire. I follow a blacksmith who uses a propane-heated forge to make knives and other small items. Here is a picture of the new forge in his workshop: https://ranum.com/badger_forge/2023/05/19/the-new-forge/ https://ranum.com/badger_forge/2023/05/19/the-new-forge/ Here is a picture of the old forge in use: https://ranum.com/badger_forge/2019/06/04/silver-in-the-forge/ https://ranum.com/badger_forge/2019/06/04/silver-in-the-forg... . Using coal/charcoal would not make it more bad ass.
tsss 3y ago
The heat and the smells are such a big part of the experience. They're really doing the students a disservice by taking that away.

by bcks 3y ago

kibwen 3y ago

That's an incredible application of induction heating that I hadn't considered. How big was the coil?

bcks 3y ago
Maybe 6 inch diameter.
- bcks 3y ago
  Ah, my bad - looking at induction forge images and links in this thread, the coil was probably closer to 3 or 4 inch diameter.
toomuchtodo 3y ago
Induction forge. https://youtu.be/P_STrnP__D4 https://youtu.be/P_STrnP__D4
- latchkey 3y ago
  Kind of wild to watch him hold the rod with his bare hands while it gets red hot.
  - dreamcompiler 3y ago
    Steel is a poor conductor of heat. You cannot do this with aluminum or copper.
    - scoot 3y ago
      You can’t do it with aluminium or copper at all. There will be no heat to conduct, so hold it as long as you like.
      - grozzle 3y ago
        A myth. Copper and aluminium won't heat on a consumer-grade kitchen induction stove, which only have a set of coils designed for ferrous metals, but restaurant kitchen professional IH stoves can use the different frequencies that heat non-ferrous metals, and a forge or melting furnace can indeed melt any metal, ferrous or not.
        derbOac 3y ago
        Why don't residential induction stoves have that capacity? Given the popularity of aluminum and copper cookware I'd think it would be pushed out. It's one thing people always bring up with induction ranges.
        grozzle 3y ago
        The electronics to drive the right frequency for efficiently heating ferrous metals (about 25KHz) are affordable. The electronics to drive the much higher (at least double?) frequencies for non-ferrous metals safely are not so affordable. It would add more to the cost than a new set of cookware. Cast iron is the king of cookware and works great on IH, anyway! You can put a few mm thick piece of steel on top of the hob and then set your copper pan on that, as a workaround.
      - japanuspus 3y ago
        This is incorrect. The magnetic flux will induce an electromotive force that will cause a current to flow in any conducting material and cause heating if this material is not superconducting. As an example, induction heating is a commonly used method in zone melting for Si-purification [0]. The effect is more pronounced in ferromagnetic materials because a larger flux is induced. [0]: https://en.wikipedia.org/wiki/Zone_melting https://en.wikipedia.org/wiki/Zone_melting
hef19898 3y ago
You can even do induction hardening. Used for complex parts, of if you want hardening with a very well defined penetration depth. The place I used to go had a gas furnace to heat the metal. A pitty I didn't find time to go there for ages now... Only downside of gas furnace, closed on on end, is the limited length of the stuff you can put in. I have an idea I want to try to forge longer things, but again, it is months now I didn't have time to get back to it...
- hacknewslogin 3y ago
  You just have to put a door on the back of the forge. Or block the back opening with a firebrick.
  - hef19898 3y ago
    Yeah, but it is not mine! Also, there is a open gas forge sitting right next to it. So, the place decided if some work and investment is done, it will be on the open forge. Which I can only support! But yeah, I just realized the last time I was there was last year before christmas... Good thing anout this is: the day I retire I will definitely not be bored at all!

1letterunixname 3y ago

Cookie-dough coffee can forge*: https://youtu.be/FmEb1YZScxc https://youtu.be/FmEb1YZScxc DIY induction heater**: https://youtu.be/wKFnk4R54ZQ https://youtu.be/wKFnk4R54ZQ * Unsafe because it depends on combustion and creates nanofines/ultrafines ** Unsafe because there's no current limiting, no temperature limiting, no grounding, and no crucible confinement

mkii 3y ago
I'm hesitant to get into physical project hobbies (e.g. low-voltage electronics, wood-working, 3D printing) because I'm afraid of all the hazards that I don't know about. Seeing these warnings (while greatly appreciated in a theoretical sense for me) just reinforces this fear I have.
- grogenaut 3y ago
  "the state of california is known to the state of california to cause cancer" - placard on jetway on way into california from origins unknown. You can't know every risk. You can be paralyzed by fear and never grow. Life is a calculated risk. Do dirty things in a seperate space from your living. Wear PPE. As others have said the risks for hobbies and work are different. Hell we may all be having mesothelioma from the atmosphere in 30 years. And sitting at indoor hobbies will also kill you from heart disease etc. You are not getting out of here alive.
- debacle 3y ago
  Start in a classroom setting. Check your local community education classes.
- mauvehaus 3y ago
  Do woodworking. The whirling blades are pretty apparent. Wear a dust mask while sanding, and take comfort that Jesus was a carpenter and didn't die of respiratory illness/failure. Don't do your own rigging or wiring, and you'll probably be fine. I do much of my own on both and I'm still ok. Watch the tommy bar on your vise, and mind your marking knife. The apparently harmless things will get you because you pay them less mind. Source: am a furniture maker. I still have 10 fingers. Haven't died of respiratory illness yet. Nor have I burned my shit down or crushed myself moving machinery. I have definitely made an unplanned trip for super glue after slicing myself with a marking knife.

ExoticPearTree 3y ago

But is it really blacksmithing if you're using real fire? I mean that's the idea, to heat metal in an open fire and then hammer it, rinse and repeat.

eesmith 3y ago
The idea is to heat metal until it can be shaped more easily, traditionally by hand tools. That does not require a fire. In Roman mythology, the blacksmith Hephaestus used a volcano as his forge. Traditionally it required a fire, yes, but that doesn't make it essential. I use silverware which is not made of silverware. As a point of definition, in general use, a forge is not an "open fire". Eg, https://idioms.thefreedictionary.com/open+fire https://idioms.thefreedictionary.com/open+fire defines "open fire" as "A fire not contained by a fireplace or stove" and https://dictionary.cambridge.org/us/dictionary/english/open-fire https://dictionary.cambridge.org/us/dictionary/english/open-... defines it as "a fire that you light outside, for example to cook on, or a fire in a space in a wall of a building, with a chimney to take the smoke away". As I understand it, blacksmithing is typically not done outside, where it can be too bright to use the color of the metal to judge the temperature, and the fire in the forge requires some sort of forced air (eg, a foot-powered bellows forcing air through a tuyere into a constrained fire). This means the forge is not an open fire. TIL blacksmithing has its own definition for "open fire", which is distinct from "stock fire". See http://www.faadooengineers.com/online-study/post/first-year/basic-manufacturing-process/679/open-fire-and-stock-fire-furnace http://www.faadooengineers.com/online-study/post/first-year/... . This means a blacksmith wouldn't say they only use an open fire.
- ExoticPearTree 3y ago
  My point was that heating metal over open fire and using tools to keep the fire going is what gives it that medieval allure and makes it to be a bad ass hobby.
  - eesmith 3y ago
    My point is that "open fire" is the wrong phrase. Just say "over a fire." Medieval blacksmiths did not use an open fire. I follow a blacksmith who uses a propane-heated forge to make knives and other small items. Here is a picture of the new forge in his workshop: https://ranum.com/badger_forge/2023/05/19/the-new-forge/ https://ranum.com/badger_forge/2023/05/19/the-new-forge/ Here is a picture of the old forge in use: https://ranum.com/badger_forge/2019/06/04/silver-in-the-forge/ https://ranum.com/badger_forge/2019/06/04/silver-in-the-forg... . Using coal/charcoal would not make it more bad ass.

tsss 3y ago

The heat and the smells are such a big part of the experience. They're really doing the students a disservice by taking that away.