Secure each steel plate into the C-clamp (one at a time) and grind down the edges with the hand grinder. Grind the edges with a side-to-side motion until they are dull.
Lay one of the 18-by-17 1/2-inch steel plates down on the ground (not a wood surface) or on a metal work bench. Position a side piece (17 1/2 by 17 1/2) along one side of the bottom plate to make a wall.
Turn on the arc welder to the highest settings. Carefully hold the tip of the welder directly onto the surface of both pieces of steel, moving from edge to edge both inside and outside, welding them together.
Repeat the previous step with the other pieces of steel, welding the sides, the end plate and finally the top (18-by-17 1/2-inch) steel plate. You will have one side free that will be the opening of the firebox, where you will place the pieces of wood. Allow the firebox to sit untouched for a day or so before use.
Things You Will Need
- Welding helmet
- Safety gloves
- 18-by-18-inch steel plate (end plate)
- 2 18-by-17 1/2-inch steel plates (top and bottom)
- 2 17 1/2-by-17 1/2-inch steel plates (sides)
- Hand grinder for steel
- Arc welder
- Work bench (optional)
- Precut and sized-to-order steel plates are available at home stores, saving you the hassle of cutting them to size yourself.