- 1). Choose a piece of sheet metal based on the size of the finished shroud you want to make. This example is aluminum, 1/8-inch thick, 6 inches wide and 36 inches in length. The piece is rectangle in shape with two 6-inch edges and two 36-inch edges. The finished shroud will have a circumference of 34 inches. One inch on each 6-inch edge will overlap the other.
- 2). Use hammer and anvil to bend the metal into a thin cylinder. Attach one 6-inch edge of the metal to the other 6-inch edge with several pop rivets. Use the vise grip to hold the 6-inch edges aligned on top of each other and drill holes for the rivets through both layers of the metal. Use a pop rivet gun to insert several rivets approximately 1/2 inch apart along the seam.
- 3). Place the metal on the anvil and use the hammer to tap one inch away from the edge of the metal all the way around the piece. Each tap should be hard enough to indent the metal and curve the surrounding area outward away from the dent. Tap repeatedly moving in gradually to two inches from the edge with varying force. Tap gradually away from the edge as you move around the piece to force a larger amount of material into the flange area. This is a trial and error type of shaping. As you tap the metal, it will be stretched and a flange will start to form. The edge of the metal will bend out and away from the center. Tapping certain areas more than others will cause the shroud to obtain an oval or rounded off square shape. The desired results will require repeatedly tapping and checking the shape as you go. Practice on a piece of scrap metal to get familiar with the affects of taping and stretching the metal if you are unsure.
- 4). After the flange is formed, drill holes for the bolts that are used for attaching the shroud to the side of the radiator. Use vise grip and hammer to form a 90-degree folded 1/4-inch lip around the outside edge of the flange to add strength to the entire piece. Fold the lip out and away from the radiator.
- 5). Use vise grip and hammer to form a 180-degree folded 1/4-inch lip around the front of the shroud. This will add stiffness and strength to the front part of the shroud. A double fold will make a rim around the edge and create even more strength.
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