Charcoal and Heart of the Fire

[NJWilliam]

I've looked around quite a bit, and have found very little about how to tend a charcoal forge.

I'm slowly figuring things out, but hopefully there's some knowledge that can shortcut the trial and error process.

 

I have dry stacked some fire bricks for a side blast charcoal forge.

The tuyere (just a piece of black pipe) is two inches above the bottom, and there is six inches above the tuyere.

So the fire pot space formed by the bricks is about five inches by five inches and 8 inches tall in total.

 

I'm using hardwood charcoal (Cowboy), that I've chopped into roughly 1 inch cubes and smaller.

 

The heart of the fire stays at 4 inches above the tuyere, and I haven't had success trying to move it up.

 

My understanding is that if I could move the heart of the fire up, it would be hotter (which is why I am interested in raising it).

 

What contributes the most to raising and lowering the heart of the fire in a charcoal forge?

 

Thanks in advance.

[swedefiddle]

I used charcoal last weekend for the first time. It sure requires lots of attention and a pile of fuel to get a big heat.

I can truthfully say that I won't go out of my way to use charcoal again.

 

Neil

[Frosty]

Welcome aboard, glad to have you. Please put your general location in your header so the guys on IFI who know how to use charcoal can visit for a hands on session.

 

Forget trying to move the fire up, raising or lowering is a sign, not a goal. Raising is what happens when you turn the heat up, NOT what turns it up. Put more fuel on the fire and turn up the air. THEN find the heart and you'll find the heat.

 

Frosty The Lucky.

[jmccustomknives]

Airflow has the larges impact.  Think of it this way, as the air blows thru the oxygen combines with the carbon in the charcoal during combustion.  The most oxygen is found where it comes in and decreases the further up in the coals (oxydizing, neutral, carborizing).  The oxidizing flame is going to be the hottest but will eat up your steel due to scaling so the neutral part of the fire is where you want to work.  The carborizing works good for heat treating. 

It takes a little practice, and with charcoal a lot of little burns to get things right. 

[Glenn]

As Frosty said, the amount of fuel does not make the fire hot, it is the amount of air that makes the fire hot if there is enough fuel is available.  With solid fuel forges, over fueling the fire is the thing to do, then add air to get the heat you want.