How to Make Homemade Curling Rocks
- 1). Unscrew the lid from an empty milk jug. Set the lid aside. Remove any price tags or labels from the surface of the jug. Wash the milk jug in warm soapy water and then rinse in it clean water. Dry the outside of the jug with a dry cloth.
- 2). Cut off any protruding tabs or lines of plastic from the bottom of the jug with a knife, making sure to wear gloves on your hands to protect them from the hard plastic. Slice along the protruding plastic as close to the bottom surface of the jug as possible without cutting through it. Smooth the bottom of the jug further by rubbing sandpaper over the surface. Wipe off any plastic bits clinging to the jug's bottom with a dry cloth.
- 3). Fill the milk jug with clean water until the water level reaches the point 2 inches from the top of its opening. Dry off any water droplets that may have splashed on the outer surface.
- 4). Place the jug in a freezer for 24 to 48 hours to allow the water to completely freeze. Remove the jug from the freezer only when it is time for use. Screw the lid back on the jug. Move the jug outdoors immediately to keep the inner layer of ice from melting.
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