Coke in forge not lighting

[QbBlacksmith]

My coke in the forge won’t stay lit how can I fix this

Edited July 9, 2021 by Mod30
Change fuel type

[ThomasPowers]

Try this, that and the other thing!  Or without details it's really hard to tell...  How is the forge designed?  A picture would help.  What type of charcoal are you using?  What is your air supply like? (Tuyre details and blower details).  How are you piling up the fuel?

This is an odd one as charcoal usually burns even when you don't want it to!

[QbBlacksmith]

Hey here’s a photo of the forge 

I have coke in the forge

[JHCC]

Charcoal responds well to a very gentle air supply. Don't over-crank your blower.

[QbBlacksmith]

Sorry not charcoal but could fuel

I feel vary stupid titling the discussion charcoal forge 

[JHCC]

Okay, what ARE you using?

[QbBlacksmith]

Coke

I had the forge lit yesterday and it burned good now it just won’t stay lit

[Frosty]

Coke won't stay lit without the blower, it'll go out in a minute or so. 

Frosty The Lucky.

[Irondragon Forge ClayWorks]

The looks of your fire grate may have a lot to do with it not staying lit. How much coke has fallen through the grate restricting the air flow? Like Frosty said without an adequate air supply coke will go out. I would remake the fire grate with slits as opposed to large holes. Something like this and be sure to give the blower a couple of cranks to keep the coke lit when at the anvil.

[ThomasPowers]

Ahh makes much more sense now.  As previously said; coke requires a constant air flow; it will go out just while you are working at the anvil otherwise.  This is particulay a problem when just getting started as people tend to take longer to do things.

That's a decent set up, any chance of getting good blacksmithing bituminous coal to use with it? Or you may want to try it using lump charcoal; but will need to modify it for best use of charcoal---you generally want more of a trench fire for charcoal.

[QbBlacksmith]

What would I need to do burn lump charcoal I had thought about it... could I mix lump charcoal and coke to have a long lasting constant flame 

[ThomasPowers]

Except that the charcoal would burn out fast leaving just the coke...

To burn charcoal; clean out the tuyere and pile charcoal over it and turn the blower SLOWLY. 

To use it efficiently make a trench forge by filling the sides of that forge with clay or a spaced double line of fire bricks or, etc. leaving a trench across the grate fill with charcoal and turn that blower slowly.

Where are you located?  Having someone showing you the basics would sure speed things up for you.

[QbBlacksmith]

But it would light the coke right then I wouldn’t have it keep going out

Powell wyoming

The problem isn’t the coke is blowing out it isn’t lightning the coke

It’s getting the coke to light

[George N. M.]

I have burned coke for the past few decades with a few modifications from using coal.  First, are you talking about the coke you have created in the forge by "baking" the green coal around the edge of the fire or are you starting with commercial coke?  If the latter, the real key to keeping your fire lit is keeping an air blast to the fire.  Check to make sure that neither coke nor clinker have dropped down into the air pipe to restrict the air flow.  Also, if you step away from the forge to do something else you have to give the blower a couple turns every minute or two to keep the fire going.

I agree that the air holes in the bottom of your forge seem pretty large.  If you can't find a replacement just a 1/4" plate with 1/4" holes drilled in it will work well.  It should look like a floor drain plate (but floor drain plates won't work because they are usually cast iron).  If you could find a steel or stainless steel one, it would work but not the thin sheet metal ones.

Mixing fuels might mitigate the problem but only experimentation will tell if it will work and what proportions will work best.  Since charcoal burns faster than coke you could have a situation where the charcoal burns out of the mix first and leaves you with a 100% coke fire.

"By hammer and hand all arts do stand."

[ThomasPowers]

There are a number of threads here on lighting coke, have you looked at them?  I get 293 hits when I do a browser search on: lighting coke site:iforgeiron.com      Including: 

How do I light my stupid coke forge?! 

lighting a forge ( Coke ) in 7 minutes

How to start a coke fire? 

[George N. M.]

PS Good to hear from another Cowboy State blacksmith even if you are in the other corner of the state.  There are a few of us around.  If you are ever down in this part of the state give me a shout through the Private Message function of this site (as long as you have had your covid vaccinations).

[QbBlacksmith]

Thank you... I just started with the coal forge 3 days ago I have 2 years of experience with a gas forge though

[JHCC]

31 minutes ago, QbBlacksmith said:

Powell wyoming

It's good to put that in your profile settings, in case it's relevant for future questions.

[rockstar.esq]

One popular trick among a group of smiths I know is to take an old soup can with both the bottom and top cut off.  You put paper in the bottom, put dry wood kindling over the paper with a piece or two of lump charcoal on the kindling, then your coal or coke fuel.  

Light the paper, put the can over your tuyere, and gently give it some air.  Once you see your first couple of floating cinders, you can start to give a bit more air, and refill the top of the now-depleted can with more fuel.  In my experience, some coke requires sustained high heat to light.  Paper and wood won't last long enough to get the coke going. 

There also seems to be a critical mass for burning coke in a forge.  If it burns down to one or two lit pieces, they won't give off enough heat to light neighboring fuel if its all just in a pile.  That get's really frustrating because the lit pieces go out if there's too little air, but too much air just blows past the fuel and cools the unlit material.  The can technique helps to focus the heat and air to where they do the most good.

Another approach that's popular in some shops is to use a gas torch to light their coke fuel in the fire pot.  It never worked for me, but I don't have an oxy-acetylene torch so maybe that's why.

[anvil]

You guys are mixing up coke and anthracite when you say coke won't stay lit. Anthracite goes out without a good air supply. Bank coke up, put a small opening thru the top to the air grate and leave the ash dump opened a little and coke will stay lit for a long time. 

It appears to me that you are burning just coke, correct? You are not burning blacksmithing/metallurgical coal. 

if this is the case, your forge is not set up to burn just coke. Like George said, you need green coal,,, or something, to hold the coke and act as a firepot. A couple of firebrick will work. They don't even need to be permanent. You can buy them from most wood burning stores or potters supplies. This is just a quick heads up. But simply said it will work. Put the  brick on each side of the grate about 6" apart. To start it, put wadded up paper in first, then a little wood shavings, but most likely all you need is enough paper. 4 sheets from a newspaper will work. Light the paper, cover with coke and give it a gentle blast. When the paper burns down, add coke from the top.

the way we did a coke forge when I worked across the big pond, we made our own brick out of castable refractory. This is a powder like concrete we made two half round shapes about 4" thick,12" long and about 8" tall. Let them dry and they are ready to use 

 

[ThomasPowers]

Breeze, coke made by burning coal in a blacksmith forge, is a lot easier to light and keeps lit easier too. Industrial coke is MUCH harder to light and keep lit!

[anvil]

When the Carbondale coalmine closed I had a source for Wyoming petroleum coke. I burnt it for about 4 years. You need paper and wood shavings to light it instead of just a wad of newspaper, but once it gets going there is very little difference between that and breeze. It will stay lit as I described above.

 

The important thing here is if this gent is burning just coke of any sort, it will not work in a flat bottomed forge without some way of containing it.

[ThomasPowers]

Good point about keep the heat contained.  Also; we all seem to have different experiences with different types of Coke: Breeze, Pet Coke, Industrial Coke, ?.  In some ways it's like how coal can differ and need different tweaking.

QbB: what is the source of your coke?   Note that most of the forges like what you are using seem to be designed for burning coal and not coke; perhaps our members in the UK that have more coke experience can make some suggestions?

[QbBlacksmith]

I don’t know it came with the forge

Is it possible to use lump charcoal instead of coal or coke

 

[JHCC]

"Coke" as such is simply fossil fuel with its volatiles driven off by heating in an oxygen-free atmosphere. Because the different types Thomas mentions have different densities, the oxygen/carbon ratio may or may not be high enough to sustain combustion.

There's a place near me that makes coke for the steel industry, but it's much too dense to use in a forge without constant airflow. They also won't sell it in quantities smaller than a rail car.

1 minute ago, QbBlacksmith said:

I don’t know it came with the forge

If that's the case, I would strongly suggest getting yourself some regular blacksmith's coal, learning to light and maintain a fire with that, and add your existing coke to that fire once it's well established. You're going to need to get new fuel eventually, so you might as well not frustrate yourself learning how to get the most out of something that you may not be buying again.