Concrete Tire Piers
To start this section I will refer you to Photo 1 to show what we are going to build in the next 2 steps. The bottom tire is the permanent mold and is filled with concrete. It becomes part of the concrete pier. The upper tire is the temporary mold which provides support to keep the concrete in place and is later removed after the concrete has cured. In Photo 5 the shadows obscure the lower tire so that only the upper tire is visible. This gives the illusion that we are working with only one tire.
Cut a 10 inch (254 mm) piece of the tar paper and fold it in half lengthwise so that you have a folded piece of tar paper that is 5 inches (127 mm) wide and 40 inches (1m) long. Position the tar paper inside the tire bead with the folded edge down and place a piece of duct tape about 2 inches (50 mm) from the end. Tape the tar paper to the tire, taping the free end of the tape inside the tire as seen in Photo 2.
Continue taping the tar paper to the tire at 3 inch (76 mm) intervals all the way around the tire. When you work your way back to the starting point, place the unsecured tar paper behind the beginning edge of the secured tar paper as seen in Photo 3.
Place a long piece of duct tape over the beginning end of the tar paper so that it is taped to the tar paper behind it as seen in Photo 4. Place the remaining unsecured length of tar paper around and behind the secured tar paper and tape the tar paper together so that you essentially have a tar paper ring. You will need to trim portions of the upper edge of the tar paper ring so that the height of the ring is uniform.
There will likely be bulges in the tar paper ring. To get rid of them use scissors to cut through the inner tar paper, in the bulging area, down to the fold and tape the cut so that the tar paper lies flat.
Note: It is convenient to use tar paper because it doesn’t readily stick to the cured concrete and is easy to remove. One could use cut up paper grocery bags instead of tar paper but it would stick to the concrete and would require a piece of plastic film to be added to the inner side of the paper before the concrete is added to the mold.
Now carefully place the second tire on top of the first tire so that the tar paper ring fits inside of the second upper tire. Cut pieces of cardboard to the same height of the tar paper ring, which in this case is 5 inches (127 mm). The cardboard is naturally stiff so roll the cardboard pieces into a roll to pre-form the cardboard into a ring.
The cardboard pieces are not connected to each other but are placed in-between the tar paper ring and the upper tire. This is done to add support behind the tar paper ring. Keep adding layers of the cardboard to fill the space between the tar paper ring and the second tire as seen in Photo 5.
Concrete Tire Piers: Some projects require a sturdy base or anchor. It is possible to easily make concrete tire piers that are heavy and secure enough to support and anchor the project to the ground. You may need one of these for a tetherball pole, or two of these for…