Hammer and Tongs: Blacksmithing 101: How to Build a Coal Forge

Blacksmithing 101: How to Build a Coal Forge

Building a coal forge is a very simple task. With a few basic tools and minimal material cost, you will be burning a healthy fire in a few hours.

A coal forge needs just a few things:

1. An inflammable table top

2. A 4-6" deep pot to hold the heart of the fire

3. Airflow to inside the pot

This is the basis of a coal forge. Manufactured coal forges are heavy cast iron firepots, with a T-shaped pipe underneath to let the ashes fall straight down and provide airflow, either from a mechanical blower or a hand-powered blower.

I began my new forge by cutting 2x4s to around 36" tall, with the sides being measured by eye. I then screwed it all together with a battery powered drill until I had the basics of my table.

Because I use an antique Champion 400 blower and Whirlwind firepot, I added a 4x4 with bracing to the far right corner.

The blower is attached to the 4x4, which is braced laterally and diagonally to the forge body. Its strong enough to hold the 75lbs blower assembly.

I then cut notches in the wood along the short side, about 5/8" deep and wide, in which I inlaid two bars of square stock 5/8".

The firepot sits on these two bars of square steel, which keeps the heat away from the wood. Soaking the wood in dissolved borax can also help mitigate any danger of fire.

The next step is to cut and install sheet metal for the table top, making sure that nothing is galvanized or painted. I then set in the firepot, and the forge is ready for its inaugural fire.