Coal Forge Going Out

[Glader Gold Fire]

I recently fired up my new coal forge I made and every thing was going fine untill about an hour or so in and the coal just sort of died. I have read that it is ash and clinker buildup. how do I clean it out without puting out my fire/coal?

[pnut]

If you turn off the blast for a little bit the clinker will solidify. Then scoot the coals back and sometimes you can hook it out in one piece then push the coals back over the tuyere. It really depends on what type of tuyere and grate you're using and also if there's a clinker breaker

[Glader Gold Fire]

my grate is a 2 1/2" plate with 3, 1/2" holes in a strait line.

[pnut]

You'll have to push the coals back off the grate and poke them clean. Have you looked at the grate used in the 55 forge? It's a piece of stock shaped like a squished Z or just a couple pieces of 3/8in round stock welded across the air inlet. Holes tend to clog but yours are pretty good sized though. 

Are you using bituminous coal or anthracite?

Pnut

 

[Frazer]

I know the coal I use (bituminous smithing coal) gives clinker that doesn't consolidate into a single mass very easily and crumbles into dust when you try to hook it out. So I have to move the hot coals out of the way and I have a wider shovel to scoop out the big stuff and a narrow one to push the real small stuff out through the bottom. That can be done well before the coals die out so it starts right back up again.

Are you using anthracite or bituminous coal? Could you share a few pictures of your forge/firepot?

[Glader Gold Fire]

it is 1/4" plate in the shape of a circle. the coal i use is called "premium nut coal".

how long does it take for the coal to go out when removed from direct air and it is just coal burning not wood?

it is 1/4" plate in the shape of a circle. the coal i use is called "premium nut coal".

how long does it take for the coal to go out when removed from direct air and it is just coal burning not wood?

[Frazer]

When you say its 1/4" plate in the shape of a circle, is the whole pan flat or do you have a depression in the center for your firepot where your air comes in?

Yep that's the TCS anthracite. It needs constant air to stay lit so it dies quickly when you push it out of the way. I know the struggles of anthracite, I used it for quite a while before I found smithing coal. Not from TSC, but same stuff. 

Anthracite can be used successfully, I can attest to that, but if you can find some smithing coal (bituminous) by you I recommend making the switch sooner rather than later. Here is a handy thread RE: use of anthracite.

 

[ThomasPowers]

"Nut Coal" is a size; not a type. Sounds like you have anthracite though.  What type of blower are you using?  Anthracite, like coke, requires a fairly constant air flow and so hand powered air is not suggested.  Interruptions in air flow will allow it to go out.  I've seen it happen just taking a piece to the anvil and then back to the forge.

[Glader Gold Fire]

i have a hair dryer

[Frazer]

Because the is a lot of fiddling around (fire maintenance) with anthracite in general, I would recommend making sure your grate is clear and cleaning it out more often. Getting rid of a little bit of ash/clinker clogging up the grates can be done quickly, allowing you to build up your fire again before the coals go out. If you let it go for too long and there is a whole lot of ash down there it turns into more of a project and your fire goes out. 

I got in the habit of always having a bag of lump charcoal around so when the fire died I could start it up again (relatively) quickly. It was an eventuality that my fire would die out at least once or twice during any given forging session, and even more than that with my first couple forge builds which had some design flaws that made the problem even worse (ie. holes that clog up too easily, a fire pan that was too shallow, limited ability to adjust the air etc.).

[Glenn]

You can add some wood scraps to the fire to help keep it going.  When the BTUs burn out of the fuel, clean ash and clinker out the forge and rebuild the fire with new fuel.  It is part of the forging process. 

Do not let the ash build up and block the incoming air.  Dump the ash that will collect in the down tube on a regular basis.

Every forge is different and you need to learn  how to use YOUR forge to make it work best.

[Glader Gold Fire]

ok thanks for all the help

and also what do clinkers look like so i dont try to reburn them

[Glenn]

Get a good fire going and throw in a double handfull of sand and dirt.  Keep the fire going and you will get clinker. (grin)

[JHCC]

Coal is shiny and solid black. Clinker tends to be more crusty and lighter in color when cool.

When you pull a piece of either out of the fire or when you cut the air flow, coal tends to stop glowing pretty quickly as the burning stops. Clinker usually stays red a bit longer, while it's radiating out the heat it absorbed from the fire.

[ThomasPowers]

Clinker can be dense and glassy, or friable and "coral like" or even ashy.  Depends on the coal, the blower, how you work the fire and what you are doing.  (I have a borax+clinker stalactite that was dependent from my grate after a long forge welding session with weird billets so lots of flux...It's up on the wall of my smithy for show and tell.)

[Frazer]

JHCC beat me to it but I'll still add my 2 cents in.

That really varies with the coal since the clinker is essentially all of the impurities that are present in whatever vein that coal was mined from.  

In my case, they are flaky conglomerates of... I don't know how to describe them.. porous lava-rock like things in the bottom of the fire. They are pretty easy to differentiate from coals by eye when hot and when cool mine are primarily yellow/white/black and crumble easily. ("coral-like", I like that description TP)

When I was using anthracite they would rarely stick together into a single mass so it was mostly flaky stuff. In some partially burnt pieces of anthracite I could actually see the veins of clinker running through it. 

Again, the clinker is going to vary depending on the coal. Plus my fire pot is lined, not bare steel, which does change it's appearance. YMMV

[JHCC]

My last three solid-fuel forges have all been lined/filled with either adobe or simply sand. When I burn anthracite, I get a LOT of heavy clinker that isn't just the coal's own impurities, but also the silica that it's melting out of the fill.

[ThomasPowers]

Don't forget that scale from the workpiece contributes too!

[bluerooster]

I have clinkers ranging from "coral" to melted blobs, and one in particular that came about when I first used the new firepot. It's perfectly round, with a 2" hole, kinda like a donut.  Actually, I've found that since changing the firepot, I've not had clinker stop up the tuyere.  But it will form a circle around it.

[ThomasPowers]

Why it was designed that way.