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BTUs, coal vs coke vs charcoal vs wood

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I recently acquired a coal forge and have been looking for a coal supplier near me. I found Henry's coal yard in Strasburg VA that has 4 different coal grades for sale. Julenut and stoker coal are both sold in bulk $310/ton. Rice coal and stove coal are both sold $6 per 40 lb bag. The price per ton is almost the same. Which is better and why?

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I have learned the coal is bitumos coal from the Pocohontas vein. Jule nut is 1.5x2.5 and varies in size. Stoker is pea sized, about as big as a thumbnail. The coal man says either is used by blacksmiths depending on their preferance. I'll decide when I can see it for myself. Thanks for your help.

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  • 9 months later...

I live out in the woods and my fire pit is a great source of charcoal for a forge. That being said, maple and oak are frequently used in my pit with the occasional cedar. Anyone ever worked with those who could vouch for it's usefulness? Should I use that or just bust out last years Christmas tree for it? (I have been drying the tree as firewood in my yard)

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Hardwood charcoal tends to last longer where softwood charcoal tends to burn hotter. Charcoal is relatively pure carbon so any differences can be accounted for by chemistry and physics. Softwoods are more porous as is the charcoal so it has a greater surface area for oxygen to contact. This produces a "higher" temperature than the more dense hardwood charcoal.

Yeah, right but so goes the old lore. I believe the preference (Ready for a little Frosty speculation?) is based on BTU/volume ratio. Weight isn't the main limiting factor to shipping charcoal, it's volume. Hardwood charcoal is denser so it has a higher BTU/cu' than softwood charcoal. If you're paying for fuel hand poled by barge up a river you're going to want the best bang per buck you can get. The barge will only hold x cu' so you want the max heat, especially if you're running smelters or foundries.

Same goes if you're paying peasants by the sack full or coaling and packing your own.

If you're making your own it's not such a big deal. With practice you can make it by the 55gl drum faster than you can use it unless you're really wasteful about it. If you're going to run a bloom smelt then you're going to have to be coaling a week in advance so might as well make a couple three retorts.

BTU output per LB. is the same for either or any well pyrolized charcoal.

Frosty The Lucky.

Edited by Frosty
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Smelters and foundries needed charcoal with a higher crush weight. Which in general meant hardwood.  If the load crushed to a solid mass you couldn't get air through it.  (and you can still find the values for crush resistance for charcoals!)

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  • 3 weeks later...

WOW! now I have a headache .......

One thing I've found over the years. 

Anything that is combustible will melt steel with enough forced air. 

I've only had my forge since winter and I've used wood,charcoal,coal. 

Before that I used a webber SS grill and mostly wood or charcoal. this was able to melt brass and aluminum with a shop vac and wood. 

I would suggest that you find what you like to forge with and use it. Then use what you can get when out of what you normally use. 

I've been slowly burning a old back porch off of one of our tenants homes ( replaced porch last April) in the forge, wood to charcoal. saves the coal.

I live in down town  Scranton and coal is hard to get. We used to have 4 coal companies right here in town, but they are gone now.

No one heats with coal anymore since they put in city NG 25+ years ago. 

That's food for thought right there, Scranton is known as coal country and even another poster mentioned 11 counties right here in NEPA are noted for the coal reserves.

Yet it's not mined like it  was even 20 years ago. 

Most of the local coal that is mined now days goes to Berwick Pa for the nuclear reactor. and a few coal fired steam plants that make electric . Berwick is were all of the power is made for this side of the state. The wind turbines all produce for Philly.  

SO if you can get coal for a good price, ANY coal use it. I live in a coal rich area and small quantities are no longer sold ( 1 ton and under)  unless you are willing to haul it yourself from over a 1 1/12 hour ride one way. 


I'll continue to forge with what I have on hand so long as it comes up to temp and does what I need it to do. 


BTW: one of the better tech threads I've read on solid fuels with the data provided by all.

While I may not have contributed to BTU, burn rate . I think I have stated just how hard it can be to get any coal in a area known for it. and that you should forge with what you have.   I have for 20 + years. Some combustibles just take more forced air and are not as efficient as others. ( something to remember with a hand blower or bellows)

PS: sorry for the long post. 



Edited by root
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  • 4 weeks later...

Love this topic, since I was thinking about this yesterday...having just started smithing (about 1-2 months ago)

I haven't used anything but store bought wood charcoal, and was second guessing my choice of solid fuel. This info finally put me at ease. 

I will say that in reference to the shop vac bellows, I use a hair dryer. It's like a travel version, but it has a 'cool shot' button I zip-tied down, which dramatically slows air flow from the low setting...and it can still melt (thinner) steel if Im not watching (lesson learned). Keeping some stand by charcoal in water helps with the flame spreading to any surrounding coal, and just keeping the fire in the pot. 

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  • 2 months later...
2 hours ago, DuEulear said:

Sorry eggwelder any time you burn anything you have left a carbon footprint. If you want to blacksmith without one you will need a large solar plant, an inverter, and an induction heater.

Well, yes and no. Certainly, burning any blacksmithing fuel (coal, coke, charcoal, or gas) produces CO2, and roughly speaking, the same amount of BTUs will produce about the same amount of CO2, regardless of fuel.

On the other hand, when we talk about carbon footprints, we're not just talking about the amount of CO2 produced, but about the impact on the long term carbon cycle. Burning coal, coke, and gas is releasing carbon that has been tied up geologically for hundreds of thousands of years, while burning wood or charcoal releases carbon that was floating around as atmospheric CO2 as recently as within the last few years. The advantage of charcoal from an environmental standpoint is that it's a renewable resource with a comparatively low net impact on total atmospheric carbon. 

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I D,

Burning hydrogen and oxygen gives water.

4H + O2 gives two H2O.

Provided, that these two gases react, solely.

Carbon has to be introduced into such a reaction to give carbon monoxide or carbon dioxide or other hydrocarbon compounds.



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  • 8 months later...

A bit off topic but.....

My late Father used coke in their tile stove in Germany growing up (pre-World War II) and always thought that coke was mined out of the ground like coal. I told him how coke was produced and the look of astonishment was something like a kid finding out the light in the fridge turns on and off when you open or close the door. My family in Germany were book publishers and knew many things from the casting of soft metals to using carbon arc lamps for photo engraving. Every day matters like getting coke for the house were handled by my Großmutter (Grandmother). I am willing to bet that without her taking care of them my Father and Großvater (Grandfather) would have would have frozen to death in dirty clothes trying to figure out how to open a can of beans.   

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  • 4 weeks later...

I stand corrected depending on how your hydrogen was generated you are right no carbon no footprint

on charcoal we are still releasing carbon that would otherwise stay locked up for years if we did not burn it so there is a footprint however small granted it is smaller than you will generate with a coal fire

sorry for the 2 year late reply i was just going over old posts


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  • 4 months later...
  • 4 months later...

I am new to blacksmithing so am here to learn. 

With respect to coal vs coke vs wood for forging metals; I read elsewhere that the switch to coke for steel manufacturing was made because coke has fewer impurities which could get incorporated into and affect the metal. 

Is that true?

Assuming it is true, I am guessing it only makes a big difference for industrial purposes such as producing special steels, surgical steel and so on. As you guys have said above, for centuries blacksmiths made quite usable metals from wood and coal burning forges. In the home forge application I imagine most people are not making their own steel from iron ore, though it is possible. If you're making a knife from an old worn out metal file, you really only need to heat it so you can work it. The steel is already made. So any fuel which can generate enough heat will work fine. 

The other consideration for people with neighbors close by would be smoke production. Coke might be a better choice for them since it produces much less smoke and sulfur. Or they could go with a gas forge. 

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"Steel Manufacturing" is rather ambiguous: do you mean the production of steel or the production of items made from steel?

With regards to SMELTING:   Coke has more impurities than charcoal; especially sulfur and they had great problems getting metal that wasn't hot short when they switched to coke,  (coal was never used for smelting for a large number of reasons of which impurities play a big part.)

They had to move to coke because they didn't have enough wood for charcoal in the UK.  So Abraham Darby figured out you could smelt with coke in the 1700's  Note the last charcoal blastfurnace in the Hanging Rock region in the USA went out of blast around WW1 it lasted that long due to the immense forests it owned and the purity of the product it produced. (I toured the remains left in the HR region during the Ironmasters Conference in Athens OH, USA).  The Charcoal Iron from Sweden has been famed for it's purity and ease of use after smelting with coke became the norm.

Now with regards to FORGING: in the West they started using coal for forging around the high/late Middle Ages, (Cathedral Forge and Waterwheel, Gies & Gies); but the way you use coal is to burn it to coke and then use the coke to heat your metal. The use of charcoal for forging has never stopped from the beginning of the iron age to now!  

Again most of the "industrial countries" in Europe ran short of wood early in the industrial revolution.  England passed laws against the building of new smelters in Elizabethan times as they needed wood for shipbuilding.

Note that charcoal and coal have about the same BTU content PER POUND but the density is much greater with coal.

A bit muddled as I'm skyping a meeting...fell free to discuss this further...

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  • 5 months later...

Thank you sir x100. You just made my day with that bit about making charcoal with wood WHILE FORGING. I have a big tank of wood chunks that I can use. I was "planning" on making charcoal with it, but I'm terrible at open methods and don't have a kiln. Thanks again, Huxley.


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You will be running 3 separate processes at the same time, wood to charcoal, charcoal to embers, and embers to heat the metal. Keep adding wood to the top to keep the level of the embers deep enough for your project.

Reconfigure the fire pot to the size fire you need, then make it deep enough for the conversion process from wood to embers.

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