Lay three 4-by-4-by-8-inch natural stone bricks end-to-end oriented vertically away from you on a level and fire-safe surface. Lay another three stone bricks end-to-end oriented horizontally to you and touching the end of the first three bricks to form a corner. Lay a final three stone bricks end-to-end oriented vertically toward you, so that a square “U” of stone is created on the ground. These are the first rows of the smoker walls. The open side will have a door attached.
Lay two more rows on top of the first so you have three rows high. On every subsequent row, place a piece of 6-by-24-inch sheet metal on the side two rows so that 2 inches of the sheet metal sticks out into the center of the smoker. These will be the shelf brackets. Build up the walls until they are 10 levels high in total.
Mix the surface-bonding cement in a wheelbarrow per the mixing instructions from the cement manufacturer. This generally requires mixing with water to a mud-like consistency.
Spread a 1/2-inch layer of the cement over the inside and outside of the stone walls, using a trowel. If you want to leave the outside looking like natural stone, use a 3/4-inch layer of cement on the inside only. At the base of the walls, grade the cement into the ground around 2 to 3 inches out from the walls. Let the cement cure for around three days, or as stipulated by the manufacturer.
Cover one side of a piece of 3/4-inch plywood measuring 26-by-38 inches with ceramic fiber, using refractory cement as the adhesive. Follow the instructions on the refractory cement label for application. This is the smoker door, and the ceramic fiber will help keep the smoker insulated, as well as protect the inside of the door. Cover a piece of 25-by-25-inch 3/4-inch plywood, the smoker roof, with ceramic fiber as well.
Measure in approximately 5 inches from the top and bottom of the door and place the long portion of a T-hinge at each point on one side of the door. Secure to the door with 1/2-inch screws through the screw holes in the T-hinge. Attach the door portion of a door latch to the middle of the opposite side of the door in the same manner.
Hold the door up to the front of the smoker. It should be about an inch shorter at the top and bottom than the brick walls. This is for ease of opening as well as providing ventilation to the smoker.
Attach the small portion of the T-hinges to the side wall of the smoker, using 1-inch screws with screw anchors intended for use on masonry construction. Attach the other half of the door latch to the other side wall so the door can open and be fastened close.
Sit your smoking meat on barbecue racks on the shelf brackets in the smoker. You can space the racks as you need.
Place an electric hotplate on the bottom of the smoker and run the power cord out the door. On top of the hotplate place your smoker box filled with soaked wood chips. Cover the hotplate and smoker box with an upside-down colander, which will act as a baffle to distribute the smoke evenly throughout the smoking chamber while protecting the hotplate from fat drippings and subsequent flare-ups.
Sit the end of a remote-read thermometer on a central rack in the smoker, with the face of the thermometer outside the smoker.
Close the door of the smoker and place the roof on top of the walls. Turn on the hotplate and heat to the desired temperature stipulated in the smoking recipe you are using. Add wood chips as necessary to the smoker box to keep a consistent flow of smoke.