Walnut Square Iron

Anthracite coal-How do I improve my technique?

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First time poster here looking for help on fine-tuning my coal usage.  This is all new to me, so I will take any advice or personal experiences that you may have.  I am just starting out with a brake drum forge and heating only 1/4 square stock and rods.  After calling around to several feed and grain suppliers, landscape suppliers and farm stores, I am not able to get bituminous coal right now.  I bought a bag of anthracite "stove coal" to get going.  I had to break up the large pieces that were about 2"-3" in size.  I start my forge with a firestarter, a small handfull of charcoal and then pile anthracite once it is going.  My tuyere is a 2" nipple that I cut down to 1",  coming up from a black iron floor flange set in the drum.  I welded 2 pieces of 1/4" rod across the nipple for a screen to keep the coal and clinkers from falling down the tuyere.  I lined the bottom of the drum with sand/clay mix to almost the top of the nipple.  I recently added a piece of expanded metal over the rods to help keep the smaller pieces from going down. 

 

I can light the coal no problem, but the core of the heat seems to move around the firepot in different directions.  I understand anthracite is a little more difficult to work with, and does not form a cave.  It seems to slide around easy and need constant piling up over the piece being worked.  When the piece is removed to be hammered and put back in the forge, re-piling is necessary.

 

Yesterday I took large pieces of coal and made an "igloo" over the smaller pieces to see if it would hold more heat in one area.  It did not really seem to work. 

 

My next thought is that maybe I need a bowl made of clay or the bottom tray of a flower pot with a hole cut out to go over the tuyere, to concentrate the coal over the tuyere.  I fished clinkers out from time to time to keep the air path open, but I really need consistency on the heat.  I am using a blow dryer for now to force air. 

 

I am also thinking maybe getting smaller nut coal next time.  l noticed that at the end of the forging session, the coal is dull gray with reddish pieces mixed in.  Is anthracite supposed to reduce to ash?  It seems like the pieces are not burning down all the way.  Maybe not hot enough?  I did get it hot enough to melt the end of a rod when I was not paying attention for a minute.

 

 

Sorry for the long-winded post.  I will take any advice on concentrating the heat to a smaller area.  Right now it feels like a shell game trying to guess where the hot spot will be next.  Thanks in advance.

 

Jon  

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I found that the grill and rods on base of fire pot work a bit better when flush with bottom (so to avoid any need for clay) ... But if you have clayed up bottom, it does same thing....

 

I was having a bit of  problem with heat and after watching one of our lady apprentices (I am aspiring to be an apprentice) stoke the fire  by moving coal around and OVER materials that was being heated she was able to create a very intense  fireball in center of forge,  also she was using plenty of air..  I think the more often movement of coal is helping it to coke up rather then just laying there not doing much... Tried this with my forge, also brake drum, (poking metal down into center of fireball) and upped my air and drawing coal over fireball improved  heat quite a bit.... IT may not be the fault of the coal, it may be you have not learned where most intense heat is in fire pot or you are not managing  the fireball well enough....  The heat does not seem to be at top of coke pile but down in the center....Also up to a point more air creates more heat, but also increases consumption rate of fuel... Also to little fuel in firepot (mound) may cause a cool fire...

 

Might want to look at this thread....

 

http://www.iforgeiron.com/topic/30887-forges-and-fires/

 

Dale

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Jon: while I'm not a coal guy per se I can do the dance. As Dale says having the grate at the bottom generally works better than having it sitting up off the bottom. Most of his fire tips are about right, different coal, different little things. Basically that's about how it works though. It also means smaller gaps for unburned oxy to sneak through to your work.

 

With fewer gaps and more coal surfaces burning you not only get more heat it takes longer to get out of the pile doing a couple things. First it's more heat hanging around longer so your steel can absorb it. Second it has to seep out through the pile so if the coal will coke it's going to. Forge coke called Breeze, is like gray popcorn and is excellent insulation so less heat can escape.

 

Lighting the coal you seem to have down pretty well but pile the coal up around it, several inches deep at least. Every once in a wile open the dome a little and take a look. You'll be able to see the heart, it'll be incandescent yellow, hot Hot HOT. that's where the irons go, straight to the heart. Below the heart is unburned oxy so keep above it! Above the heart is lower temps and can be useful for some things, say controlled heating for tool steel, etc.

 

Find yourself some larger stock, 1/4" cools really fast and if you're doing like so many follk do and laying your stock on the anvil THEN hitting it you're losing heat before the second maybe third blow. Find yourself some 3/8" sw or 1/2" rd. about the same size actually, figure the cross sectional area and you'll see what I mean. That's what counts, the volume you're working. double the diameter and square the volume. Anyway, it'll stay hot longer and mistakes will happen more slowly so you'll get more hammer time for the work and time at the forge.

 

I'm sure some properly experienced coal burning guys will sing out soon but I'm a talky guy and . . . Saved you from another long ramble. Well, from here on anyway. <grin>

 

Frosty The Lucky.

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Ok, thank you Dale and Frosty.  Some good tips here.  I think my fire is too shallow and too cool.  The grate is just about level with the clay/sand mix.

 

Frosty, yes, the 1/4" round stock does cool quick, but for my particular project, I need this size.  I keep two rods at a time in the fire and switch back and forth.  I know it is not efficient moving from the forge to anvil, but it is manageable and less waiting for one rod at a time to heat up.  I do have a few RR spikes that I worked a few weeks back, the working time out of the heat was longer.   

 

Dale, I did see that thread before, there may me something to it having the piece to close to the air blast and cooling the piece down.  I think a dimmer switch is needed to better manage the air flow.

 

I am going to crush the coal down a bit for more surface area and build up a clay/sand ring to keep coal around the grate.  This may be 4-8" inches in diameter.  My initial thinking was to buy bigger coal, and crush it down to a size that I felt would work best and buy that size next time. 

 

I will admit the way I am burning the coal, I can see right into the core of the heat to see if the metal has changed to orange.  I'd say more coal is needed on top to insulate.
 

 

This is so different than burning a woodstove.  I may also need to break some wood burning habits and manage the mound different. 

 

Jon

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Yes, a LOT different than a wood stove, almost no parallel in a practical sense. You'll get it though, just part of the learning curve and it ALL ties together at some level. There is NO bad knowledge

 

Have you tried calling a local farrier and asked where s/he gets coal? Even if s/he doesn't use coal s/he'll now who does and answer your question or give you the name/number of someone who can. Heck s/he might invite you on a job so you can watch how s/he manages the fire.

 

I should've thought of that right off, sorry for the brain fart. <sigh> I'm an old yellow pages, ask off the wall questions guy. I've found people really like being helpful even when it's not their field, they usually know someone who's a step closer. It's never taken me more than three steps to find THE guy. Believe it or not the internet is actually harder for local things.

 

Frosty The Lucky.

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In the intro to blacksmithing class i took, they had us make both a punch and chisel out of 5/8" or so coil spring steel.

One of the instructors cut the coil spring up with a die grinder into half coil chunks. Then dropped 2 on each of our anvils and said, make them straight. That took the better part of an hr.

You really got time to stoke the coal, and hammer the coil due to the largeish size. It was also a great project to show how to use different weights of hammers as the little ball pein that many people chose to work the smaller 1/4" material earlyer in the morning was woefully inadequate for the coil project.

that lesson then ends with a hands on lesson on tempering.

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Yes, a LOT different than a wood stove, almost no parallel in a practical sense. You'll get it though, just part of the learning curve and it ALL ties together at some level. There is NO bad knowledge

 

Have you tried calling a local farrier and asked where s/he gets coal? Even if s/he doesn't use coal s/he'll now who does and answer your question or give you the name/number of someone who can. Heck s/he might invite you on a job so you can watch how s/he manages the fire.

 

I should've thought of that right off, sorry for the brain fart. <sigh> I'm an old yellow pages, ask off the wall questions guy. I've found people really like being helpful even when it's not their field, they usually know someone who's a step closer. It's never taken me more than three steps to find THE guy. Believe it or not the internet is actually harder for local things.

 

Frosty The Lucky.

Great advice Frosty.   I know of one local blacksmith I am sure I will eventually meet and see where he sources his from if he uses it.   Funny story is that I called around and two farm supply stores had bituminous coal as I asked for it specifically and said "soft coal".  Well, I went to both and they only had anthracite.  I will stick it out and figure what I need to do differently.  

There is a supplier outside of Boston, about 45 minutes from me, but the anthracite is only 15 minutes from home.  NH may have some smaller farm supply stores with bituminous.  Hard stove coal is readily available up this way from many suppliers.   

 

Jon      

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Yes, a LOT different than a wood stove, almost no parallel in a practical sense. You'll get it though, just part of the learning curve and it ALL ties together at some level. There is NO bad knowledge

 

Have you tried calling a local farrier and asked where s/he gets coal? Even if s/he doesn't use coal s/he'll now who does and answer your question or give you the name/number of someone who can. Heck s/he might invite you on a job so you can watch how s/he manages the fire.

 

I should've thought of that right off, sorry for the brain fart. <sigh> I'm an old yellow pages, ask off the wall questions guy. I've found people really like being helpful even when it's not their field, they usually know someone who's a step closer. It's never taken me more than three steps to find THE guy. Believe it or not the internet is actually harder for local things.

 

Frosty The Lucky.

 

Yes never abandon the YELLOW PAGES.... Let the fingers do the walking.... And so on....

 

Dale

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Meader Supply in Rochester NH has good blacksmith coal.

1-800-4HORSES.

Real good people and no sales tax in NH.

Buy enough of it and pay no shipping.

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Thanks so much George, valuable information there.  That is within driving distance for me.

 

 

On a sidenote: I built up a lip made of clay and sawdust in the bottom of the forge which will help keep the coal more central.

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Just a quick update.  I made the clay ring around the tuyere about 6" in diameter and about a half inch higher than the opening.  I used a firestarter, just a little charcoal and went right to anthracite.  Wow, what a difference.  The concentration of heat stayed in the middle and the temperature was really hot.  All the heat was contained to the center.  After a while I had to shut the blower down. It worked really nice.  I just kept adding coal to make a mound and it works fine.  I just need to build up more clay to the level of the ring as I used sand around the edge today.  It was a much easier session.  I will stick with anthracite for now.   
 

 

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Really pile the coal around the tyure making what they call a duck nest.  Should be 4 to 5 in high and about 12 in dia.  Wet it slightly and pack it down.  This will keep the fire from spreading.  Your working area will be the center 4 to 5 in.  Add green coal around the edges of the work area so they can coak up and rake them into the fire as needed.  Keep the fire as deep as possiable.  I often use fire brick instead of a duck nest.  Use the brick on the sides about a brick length apart and pile the coal up over the top of the bricks.  Wet the green coal down using a sprinkler can.  This will help the coaking process and keep the fire from spreading.

Hope this helps.  Keep trying and don't give up.

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Just a side note-anthracite has been historically used by smiths. A while back the Anvils Ring had an article on it, with references of smiths in the 1800's writing about it-enthusiastically. A friend of mine-Fletcher Coddington of Arrowsmith Forge-uses it exclusively. If you are in an area where smoke or bituminous supply and cost is a problem, you can use anthracite with no issues-and fire weld with it (I've done it).

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Really pile the coal around the tyure making what they call a duck nest.  Should be 4 to 5 in high and about 12 in dia.  Wet it slightly and pack it down.  This will keep the fire from spreading.  Your working area will be the center 4 to 5 in.  Add green coal around the edges of the work area so they can coak up and rake them into the fire as needed.  Keep the fire as deep as possiable.  I often use fire brick instead of a duck nest.  Use the brick on the sides about a brick length apart and pile the coal up over the top of the bricks.  Wet the green coal down using a sprinkler can.  This will help the coaking process and keep the fire from spreading.

Hope this helps.  Keep trying and don't give up.

 

 

Good points there Backwoods.  I think I am just getting over the hump for maintaining the fire.  When I am pretty comfortable with it, I will use the above info for better managing it.  I will definitely keep at it.

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Just a side note-anthracite has been historically used by smiths. A while back the Anvils Ring had an article on it, with references of smiths in the 1800's writing about it-enthusiastically. A friend of mine-Fletcher Coddington of Arrowsmith Forge-uses it exclusively. If you are in an area where smoke or bituminous supply and cost is a problem, you can use anthracite with no issues-and fire weld with it (I've done it).

 

 

I am beginning to like it.  Forge modifications were necessary after seeing the performance on the first few runs.  It definitely gets very hot and I think I will be fine using it.  The low smoke is also a plus working near neighbors.

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Your coal is still too big.  The stuff I work with is about an inch across.  Also don't give up on the bituminous coal.  You will be amazed at the difference it makes.  It is much easier to work with (IMO.)  I  pay  0.50$ a pound for bituminous rather than 0.05$ a pound for anthro, and do it gladly because of how much easier it is to work with. 

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I worked with anthracite at the beginning because it was all i could get. Takes a lot more air than bitumous, harder to get started, and yes, it doesn't coke really or form the "cave".

 

Air control was a big issue, too little and it went out or wouldn't start, too much and it stayed around welding heat all the time, which made for short reheats, but used up a lot of fuel and would burn the steel in a minute if you let it.

 

Smaller anthracite is definitely easier (aside from breaking it up, which is a pain), no more than around an inch and a half across. For my money though, much better control with bitumous, and I use so much less fuel that that alone made up for the extra expense.

 

For starting it, I like to use wadded up paper with some lump charcoal mixed in. Light, wait for the paper to catch good, turn on blower, add the charcoal, wait for it to catch good, add coal over the top. Should be ready to go in 1-2 minutes. Good luck!

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Your coal is still too big.  The stuff I work with is about an inch across.  Also don't give up on the bituminous coal.  You will be amazed at the difference it makes.  It is much easier to work with (IMO.)  I  pay  0.50$ a pound for bituminous rather than 0.05$ a pound for anthro, and do it gladly because of how much easier it is to work with. 

 

 

I'll grab nut coal next time, if I can't get up to Meader Supply like George mentioned above for the bit. 

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I worked with anthracite at the beginning because it was all i could get. Takes a lot more air than bitumous, harder to get started, and yes, it doesn't coke really or form the "cave".

 

Air control was a big issue, too little and it went out or wouldn't start, too much and it stayed around welding heat all the time, which made for short reheats, but used up a lot of fuel and would burn the steel in a minute if you let it.

 

Smaller anthracite is definitely easier (aside from breaking it up, which is a pain), no more than around an inch and a half across. For my money though, much better control with bitumous, and I use so much less fuel that that alone made up for the extra expense.

 

For starting it, I like to use wadded up paper with some lump charcoal mixed in. Light, wait for the paper to catch good, turn on blower, add the charcoal, wait for it to catch good, add coal over the top. Should be ready to go in 1-2 minutes. Good luck!

 

You are right about the air.  I did get it really hot yesterday and went through a bit of coal.  I am chopping up the stove coal in a bucket with a "mutt" chopper and it works well.

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