Anthracite Coal

[dickb]

I am using a coal forge with an old hand cranked blower.
I have available Pea size anthracite coal and Nut size anthracite, both available bagged at about fifteen dollars per hundred pounds. Until now, I have been using the pea size.


Can anyone give me an idea if it's a good idea (or not) to use the nut size?

I see lots of articles on how to manage a soft coal fire, but I think these don't apply to using anthracite. I don't think it actually "cokes" and I don't think it packs into a solit mass.
Am I correct?

In general I'd like any advice available on managing an anthracite forge.

Thanks

[Pat Roy]

I don't know anything really, about anthracite. I am able to get bituminus blacksmith coal locally. It is probably bigger than pea or nut and it cokes up well and masses up pretty well. I pay $15 per 55# bag.

[ThomasPowers]

Where the fire gets to neutral or reducing is a function of the fuel size so if you tend to like shallow fires or plan to do a lot of welding or knifemaking then the size may make a difference to you.

(smaller fuel means more surface area to scavenge O2 before getting to your workpiece; but gets to be a pain to work with if it gets too small---blows out of the firepot, drops through the ash grate, etc...)

[dickb]

Thanks,

Well i understand about neutral and/or reducing fire, but I'm not sure I understand "inverse proportion"

The firepot is about 10 X 12 inches and about 5 inches deep. I do plan to do a lot of welding.
I usually fire with the coal about 2 inches above the top of the pot.

Given this info, which size (Nut or Pea) would you suggest?

Thank you from a more or less Newbie.

Where the fire gets to neutral or reducing is an inverse function of the fuel size so if you tend to like shallow fires or plan to do a lot of welding or knifemaking then the size may make a difference to you.

[ThomasPowers]

Sorry I probably have it backwards; what I mean is that the smaller the fuel the shorter the stack of it necessary to reach reducing or neutral atmosphere in the forge.

IIRC Rehder in "The Mastery and Uses of Fire in Antiquity" calculated that for a smelting furnace the reducing area was about 12 times the mean fuel diameter above the tuyere.

I've never used anthracite so I can't advise you, except that if you give the large stuff a try and don't like it it can be reduced in size...

[matto]

if you are getting 100 plus pounds for $15 and it does not coke it is not anthrosite, it is liginite. anthrosite has very very low moisture and hardly any ash content
it is the next best thing to coke. it has great coking ability. as for size you can always make it smaller. try the bigger size if you don't like it bag or box it and hit it with a hammer. then you have pea size.

[Francis Trez Cole]

anthracite is the type of coal used for heating it will burn with just a draft I have used it along time ago. Now I use bitouminious it is the only way to go. As you burn coal it turns to coke that is the point you can begin forging. During the burnning off stage you are burnning off the impurities and contamanits.

[Clam River Coal Forge]

I agree with the rest try it out! I have so far retrived coal from a river and now I have been give coal that has been exposed to th weather for over 30 years. Some is soft and some is hard some are big chucks like 12 inches square that I have broken up. The coal that I am getting this week has a lot of slack (small pieces) I am going to try it this weekend and see how it cokes. I do not think one should settle for a certian size a mix would give you some variability with fire control.

[john_zxz]

Hi Dickb. I too use anthracite for forging and forge welding since a couple of years. It works great for me even if it doesn't coke up like coal.
The anthracite I use is from Keystone company. It comes from mines in Pennsylvania. It is anthracire sold for home heating. It does not smoke but smell a little bit weird.
I'm using nut size because pea size tends to fly too easily in the shop and it blocks my air entry too often.

To light it up, I use charcoal. I tried wood but it tooks me like 30 minutes to get it hot enough to add anthracite. So I switched to charcoal wich burns hotter.
The method I use is to put a ball of paper in the firepot, then I add 2 handfull of charcoal (to cover the paper ball). Then I light the paper and turn the hand crank blower slowly. When the charcoal has turn yellow, then I can add a little of anthracite.

Not too much like you can put with coal because the fire will turns down. Then when the anthracite has began to turn orange, I keep adding more and this is the moment where I switch from hand crank blower to electric blower. (The reason is that my electric blower is too powerful for the beginning of the fire. The paper ball would jump in the air if I turn it on too early.)But you can stay with hand crank the whole process. Its just that you have to crank more often than with coal, but you know that already, your using pea size.

After that, you keep adding more and more anthracite as the burned anthracite is red hot. You have to do it a couple of time to get used to the "when to add more" thing. My fire is usually 2 to 3 inches over the firepot. By experience, if my fire is too small, the anthracite has tendencies to turns down easily. So I make bigger fire.

Oh and you can't add water like coal as it just kills the fire because there is no coking process. It works like a charcoal fire.
I made a video on youtube where you can see how I light it. It is a little dark, sorry it was filmed on a photo camera. In the video I use electric blower all the time. I was lucky that the paper stayed in the firepot.

Hope it helped you.

john_zxz

[John B]

Don't you have any method to control your air blast when on electric blower, like a slide valve or speed controller?

If you haven't, you may be wasting fuel.
 

[thecelticforge]

If you have some of the harder coal that does not coke well if at all and a lot of slack with it I recommend screeding it first to get rid of the small bits as they will tend to stay at the side of the fire pot and not burn leaving you with a tunnel of fire in the center that burns up very quickly.

I recently got several ton of free coal from an old basement here in town. It was hard, dusty, and full of seat rock. I tried it in its natural state (as is) first and it was a horrid experience.

I placed it on a table of expanded steel and raked it around well till almost nothing fell through, then I washed what was left on top with water. It did much much better after that.

[john_zxz]

To John B

No I don't have any air regulation or speed controller. When I'm forging I just shut down the fan and restart it when I put metal in fire. It may eat a lot of electricity every time I turn it on...
I should put a speed regulation on the fan, but not sure how to do this...I'm not very into electrical things. It is a fan of an industrial heat system that was a gift.
I disassembled the heater thing and now it is just a big squirrel cage blower with a motor. I guess I have to know the amps or watts of the motor to choose the right dimmer.
Hm...not sure if the label is still there. If I am not able to do this, I'll probably go with the slide valve.

[ft_layne]

i use anthracite but have difficulty starting it burnes hot.

[Thurgoz]

Layne is spot on. smart man

[Francis Trez Cole]

when I first started anthracite was all I could get I personally would use the nut size. Pea size is small. When I got it I payed $6.00 for a 50 lb bag. it was big pieces larger than softballs. Had the kids break it up with hammers. Kept them busy. You will be able to weld with it Use the bee hive method pile it up wet it and you will have not trouble. slow steady heat