Cut the radishes and carrots into thin matchsticks
Place the carrot and daikon matchsticks in a large bowl and sprinkle with the salt and 2 teaspoons of the sugar.
Squeeze and knead the matchsticks for three minutes with your hands, expelling water. They will soften and water will accumulate in the bowl. Stop kneading when a piece of daikon can be bent, one end touching the other, without breaking.
Transfer the matchsticks to a colander, drain, and run under cold water briefly. Press down gently to remove any excess water.
Remove the matchsticks to a quart jar for storage.
In a large bowl, combine the rest of the sugar, vinegar and 1 cup water. Stir until the sugar dissolves.
Pour this mixture over the vegetables. It should cover them. Allow the matchsticks to sit in the brine for at least an hour, but, in the refrigerator, they will keep for a month.