Put cucumber spears in a large container. Stir pickling lime into 1 gallon of water in a large pitcher until lime is dissolved; pour over cucumbers. Refrigerate for 24 hours.

Drain cucumbers and rinse well; return to large container. Pour enough cold water over the drained cucumbers to cover. Soak at least 3 hours; drain. Transfer cucumbers to a large pot.

Stir 1 ¼ cups of vinegar and 1 ¼ cups of water together in a bowl; add cinnamon red hot candies. Set aside to soak, stirring occasionally.

Stir 1/2 cup vinegar, red food coloring, and alum together in a bowl until alum is dissolved; pour over cucumbers and add enough water to cover. Put a lid on the pot, place the pot over medium heat, and bring to a boil. Reduce heat to low and simmer for 2 hours; drain and return cucumbers to the pot.

Pour cinnamon candy mixture into a saucepan; add sugar and cinnamon sticks. Bring the mixture to a boil; cook and stir until the candies and sugar are dissolved completely into a syrupy liquid. Pour the liquid over the drained cucumbers. Refrigerate 8 hours to overnight.

Drain liquid from the cucumbers into a heavy saucepan; bring to a boil and pour again over the cucumbers. Refrigerate 24 hours.

Drain liquid again from the cucumbers into a heavy saucepan; bring to a boil and pour again over the cucumbers. Refrigerate another 24 hours.

Heat cucumbers and syrup to a boil.