Novice coke questions

[Joel OF]

Hi all, I'm a complete novice with three questions/statements about getting a coke fire going in my brake drum forge without using shortcuts like BBQ lighters. I'd really appreciate it if you'd tell me if my theory is correct as I want to make sure I haven't been fluking it.

My most successful method so far has been to make a small wigwam shaped fire, then add charcoal when there's a good flame, then add coal once the charcoal has lit, then add coke when the charcoal is burning down and the coal has lit. If the pieces of charcoal/coal are big then I break them down into smaller pieces.

1 - It's hard to get coal/coke at the edge of the brake drum to light if the fire and charcoal has only been placed in the middle, so spreading charcoal to the edges helps make sure there's enough flame at the edge to get the coal/coke to light.

2 - Once the coal is lit and there's not much charcoal left I shouldn't be stingey with how much coke I put on as it takes a while to light, and a decent mound helps cacoon the heat in.

3 - It's difficult to get coke to light from charcoal alone as the amount of air that coke needs would burn out the charcoal before the coke has had time to light.

Even though I'm a complete novice I want to follow traditional methods as much as possible and would like to steer clear of shortcuts like BBQ lighter blocks as there's no satisfaction in using them and I don't want to become reliant on them. Having said that I kinda feel like I'm "cheating" using charcoal, should I feel like that? Is there a reliable way of getting coal to light from a fire in such a small forge without using charcoal?

Any help would be really appreciated. Sorry if I've put this thread in the wrong forum.

[calala]

Kurgan I simply wrap a couple of hand fulls of charcoal in a sheet of newspaper, place in the forge light the paper and add air, when the charcoal is burning add the coke. I don't use coal where I am because of the smoke problem. Please remember all things require air to burn and lots of it.
If on the odd occasion I don't have any charcoal I use twigs or such in its place. Hope this is of help. Cheers John. :)

[Joel OF]

Hi John, thanks for the reply. I tried that method the other day but I had no joy, I don't know why. Do you add coke as soon as the charcoal has lit or do you wait a while?

[calala]

I wait till the charcoal is burning but I must stress it will need air don't be put off by a few sparks If the fire starts to smother when you add the coke it just needs more air. :) Cheers John

[Joel OF]

Thanks John. I'm using a hair dryer as a fan so I've got plenty of air when needed. I very quickly learnt that short sleeves aren't ideal - smashing up charcoal into more manageable sizes really makes it spark! A blizzard of sparks!

[calala]

Kurgan I should have told you I add the coke around the side of the charcoal fire slowly filling it in, if a blowhole appears just fill it in with coke. Cheers John.

[Joel OF]

Ahh, now that relates to one of my questions...should i put charcoal at the edges too? If not, how do i get the hot coke coals to spread without putting them out? Loads more air? I'm finding that if i only have hot coke in the middle it's too small an area to be useful because as soon as i put in/take out the piece of steel the coke collapses almost goes out.

[Dan P.]

I've used charcoal to light a coke forge before. Outside of using the gas axe it's my favourite method.
In terms of traditional methods- the first smith I worked for, an "old boy", used to light his fire by sticking the business end of an arc welder with a big gouging rod into a bed of coke, return lead attached to the leg of the forge. Not recommended!

[Joel OF]

Gas axe? What's that?

[Dan P.]

A gas axe is an oxy-propane (or oxy acetylene) cutting torch. The term "gas axe" benefits from only having two short syllables.

[ThomasPowers]

Gas axe was used to refer to the crudeness of the cut too as in the old saying "Measure with a micrometer, mark with chalk, cut with a torch!"

[calala]

Kurgan, as soon as the coke in the middle is burning, back off the air so the fire will spread. The fire will collapse in the middle because the charcoal will burn up, this is not unusual. When you first add coke it should be approximately twice the depth of the pot in height this will allow for the charcoal burning off. I wish I was there to show you it is very easy, as they say "a picture is worth a thousand words" :)

[ThomasPowers]

Note too that with coal or coke you don't get an edge to edge fire like with charcoal---most of that's wasted anyway. What you get is a central hot spot that you work your metal in---the width of the hot spot is usually dependent on the configuration and size of your tuyere

[Joel OF]

Thanks for all the replies folks. Since posting this I've let rip on the brake drum forge a few more times and am getting to grips with it much better. One thing though that's still bugging me is I seem to be getting through a lot of coke, which makes me think I'm doing something wrong, but at the same time I'm rationing the air supply to only when it's needed...so...it's kinda like the coke burning off quite fast, but if I reduce the air supply it's not enough to keep it lit. Any advice?

(P.S. I guess this depends on what coal you're using, but...how long does it take for coal to coke? I keep seeing/reading about coke being put at the edge to coke but no one ever says how long that takes?! 1 minute? 1 hour?)

[ThomasPowers]

till it does; but not too long as you can coke up coal fast enough to keep the hot spot full of coke

[rockstar.esq]

I found that coal cokeing around the fire tended to form at the bottom of the brake drum. The flat bottom of the brake drum tends to create a pyramid shaped fire. If you look at commercially made fire pots, they're all sloped towards the inlet.

In use this tends to allow the coked coal at the perimeter to slide in towards the inlet as the center coke is consumed. Some folks put clay in a brake drum forge to create this slope as well as to insulate the drum.

I got in the habit of prying the coked coal at the bottom towards the center. Every ten minutes or so it'll need it again. Don't forget to pull out the clinkers or they'll just choke it down.

I used to use a blower much like a hair dryer. I found that higher air speed seems to consume more fuel with less heat. I've also read a few comments saying that fast air creates more clinkers. Most of the crank blowers are similar to water pumps they produce high volume at lower pressure. Currently I use a box bellows. I enjoy the quiet but the crank blowers are the pinnacle of design as far as I can tell.

I have found that coke is sometimes a struggle to keep lit. I used to use coke exclusively but cutting it with coal has made it easier to keep the fire lit without constant draft.

I've learned to open the ash dump when I have the kindling going. I don't use charcoal, I get the kindling going then I pretty much smother the thing with green coal and coke. I punch in a center hole with my poker and the fire acts like a mini volcano. Blowing with the ash dump open keeps me from generating hurricane force winds that just blow the coal out. If you think of it as letting the coal "soak" in the heat like a billet of steel, You'll quickly find that it catches fire once it's hot enough. Rushing things with air blast has prevented me from getting the forge going on many occasions.

The draw of my firepot with the ash dump is almost enough to get the kindling to start the coal. I only start blowing when there's green smoke showing that the coal is heated up.

[dickb]

I ran a forge on coke a couple of days ago for the first time. On my first attempt to get the coke to burn I did not use enough kindling wood. The coke did not begin to burn before the kindling wood burned out.

The next time I used a lot of kindling wood, just a few slivers of broken up wood and when these were burning, I added some more, a little bigger pieces and more of them, and finally enough scrap construction wood scrap to fill the fire pot.

I was reasonably sure the construction wood scrap would ignite so I immediately piled on the coke and using a and cranked blower started cranking. When you blow air through a wood fire you get a very hot fire, easily capable of igniting the coke.
The fire pot is about 1o inches by 12 inches and around five inches deep.


Three important points,
1 use plenty of kindling wood
2 use as much air as you can get without blowing out the burning kindling.
3 the coke should be in small pieces averaging about the size of a walnut, approximately one cubic inch. Break it up to this size if necessary.

Good luck,

Dick B