I was inspired by this instructable on making a shiny ball out of aluminum foil to try making other things out of foil. These rings feel solid and look cool, and they are easy to make. You can feel like a blacksmith making them, without using heat or special tools.
Step 1: Cut and Roll the Foil
For this project you will need aluminum foil, scissors, a hammer, a smooth surface for hammering on, a piece of 1/2-in-diameter metal pipe, wire cutters, super glue, and clear nail polish.
Cut a piece of foil about 4 inches wide and 9 to 11 inches long. Roll it up along the short end into a small tube. If you want to make a smooth ring, crinkle the tube and then twist it up, as shown. Instructions for a more crinkly-looking ring will come later on.
Step 2: Start Shaping the Foil
Take your hammer (one with a smooth head, if possible) and begin gently tapping the foil on a smooth surface. A concrete floor or a solid metal surface works well. Turn the foil as you tap, to create a smooth, dense rod. You can start pounding harder as the rod becomes denser.
Step 3: Shape Into a Ring
Bend the rod around your pipe. It is okay if the pipe isn't exactly the size of your finger, because we will adjust the size later. Start hammering the foil around the pipe so it becomes flattened into the ring shape.
Step 4: Flatten the Edges and Continue Shaping
Pull the ring off the pipe and very gently flatten the edges with taps of your hammer. Put the ring back on the pipe, and flatten it against it again. Repeat until you are satisfied with the shape of your ring (about 2-4 times).
Step 5: Sizing
Wrap the ring around your (or the recipient's) finger to determine the size. Cut to size with wire cutters, so that the two ends will meet.
Step 6: Join the Ends
To join the ends, you can either try to insert one end into the other by peeling the foil open on one end, or you can just have them touch. The first method is stronger but more difficult.
Cut a very thin strip of foil, about 1/4 in wide and 1 in long. Fold it so that there is only a seam on one side.
Put a dab of super glue (caution! don't glue fingers!) on one end of your ring and keep pressing the other against it until a bond is formed. While you are holding it, wrap the foil strip around the seam, super gluing it into place (you only need a tiny amount of glue).
When the glue is dry, your ring will be pretty sturdy.
Step 7: Polishing
For a dull shine, rub your ring on smooth concrete or a rock.
For a high shine, rub your ring on smooth metal, such as a metal bolt.
Try to get all of the rough spots as flat as possible, so you will have a nice, smooth ring. You can get creative. Test different surfaces out on the bits you cut off when sizing the ring.
Step 8: Put on the Coating
Coat your ring with 2-3 coats of clear nail polish, letting it dry between each coat. This will make the ring smoother to the touch and keep it from leaving aluminum oxide residue on your fingers. I'm sure there are many other coating substances that could be used other than nail polish, but that is what I had on hand.
Step 9: All Done!
There are many other things you can try with these rings--crinkly texture, adding color, and different rings styles. I'll go over these briefly.
Step 10: Crinkly Ring
Once you've rolled up your foil cylinder, start twisting it without crinkling. Hammer it flat, rather than round. Don't hammer it too much or you will lose the texture. Turn it on its side and hammer it into a square rod. Shape into a ring and hammer gently around the pipe. Hammer the edges then complete the ring as with the smooth ring.
Step 11: Colors
To add color, you can use colored sharpie markers to totally color over your roll of foil before twisting it. Let it dry for 10 mins before twisting. Use the crinkly ring method, and the color will be visible in the seams. However, do not coat with nail polish. The colors will smear. I am planning to use clear spray paint, but I haven't tested it yet.
Step 12: Different Styles
Super glue is not needed if you use a wrap ring style. Use a foil cylinder that is 1/2 inch or so longer than the circumference of your finger. Hammer the ends of the ring flat and rounded.
You can also try making a bracelet.
Very small rhinestones can add a nice touch. Just don't try to hammer a little dent in the ring to put one in; it doesn't turn out well.
You could also make a chain, maybe for a necklace--or a jailbird costume.
Let me know in the comments what ideas you come up with!