Slice the cucumbers by hand, about a quarter inch thick. As thick or as thin as you want. The thinner you slice the more brine they will hold. If you use a thicker cut, the end result is less soggy and crunchier and will keep in brine longer too.
Meanwhile, combine the water, salt, vinegar, sugar and pickling spice in a medium saucepan and bring to a boil. Remove from the heat and let cool.
Put the cucumbers in a medium bowl and add the pickling solution; they should be completely covered by the brine. Cover and refrigerate for three to six hours before serving. The pickled cucumbers will keep in the refrigerator for up to five days.