Make sure to use a non-porous, ceramic stock pot or
a 1-gallon glass jar for this as the liquid will pit non-coated aluminum stock pots. Discard the pickling lime and water Soak the cucumber rings in ice water for about 3 hours.
In a small bowl, mix 1 cup of the vinegar with food coloring and alum, Add some water.
Pour this mixture over the top of the cucumbers and add more water to cover.
Set on the range over medium-high heat and bring to a simmer, Reduce heat and continue to simmer for about 2 hours. Pour off the liquid when cool enough to handle easily, and discard.
Meanwhile, in a saucepan over medium-high heat, combine the remaining 2 cups vinegar, 2 cups water, sugar, cinnamon sticks, and red-hot candies.
Bring the mixture to a hard, rolling boil for about a minute, making sure to stir constantly. Pour the mixture over the cooked cucumbers and let stand 24 hours. Pour off the liquid, but reserve and reheat it in a saucepan over medium-high heat.
Bring the liquid to the boil again. Place cucumber rings in 6 to 8 sterilized pint jars Pour the hot pickling liquid over the top of the cucumbers.
Make sure to use self-sealing lids that have also been sterilized with the rings. Leave on the counter overnight to seal, then store in a dry, dark pantry. Serve straight from the pint jar.