Toy cars, collectibles and home decorations are just a few things made from diecast metal. The fabrication process uses lead metal, often mixed with another type of metal like aluminum or zinc. The liquid metal pours into a mold, creating the shape of the item. When the diecast metal becomes broken or otherwise damaged, a small amount of glue solves the problem.
Epoxy glues consist of two products that when combined create a strong hold. The epoxy typically comes in a plastic syringe with each type of adhesive found on one side of the syringe. You may find epoxies that come in two containers and require that you mix the two. Mix the adhesive epoxy on a piece of old newspaper or printer paper and keep it close to the diecast. Apply the adhesive with a small brush or toothpick, which keeps you from using too much adhesive on the piece.
Metal glue works well for diecast repairs because the adhesive specifically works on metal surfaces. As metal glue is typically gray and resembles the natural color of the metal, so use the glue only on diecast pieces without any bright colors or high levels of decoration. Apply a small amount of the metal glue to one side of the diecast and press that side against the unglued portion. Hold the metal together until the glue begins curing and is strong enough that it holds together on its own.
If the glue does not adhere to the diecast, wipe off the excess glue then lightly sand down the surface of the diecast with fine grit sandpaper. Sand both sides and apply a small amount of glue. Sanding the piece removes the excess glue and roughs up the surface slightly, giving the glue a greater surface area to which it can adhere. Hold the pieces together for at least 60 seconds and gently transfer the item to a flat surface. Depending on the shape and size of the piece, you may need to use small clamps to hold the piece together until the glue dries.
Do not use any type of white glue or clear glue on diecast, including super glue-type products. These glues drip as they dry, leaving unsightly marks behind on the piece. These glues are also not designed for use with diecast and may not work as well as metal glues or epoxies. You may find that you must glue the item again in the future.