I bring up the subject of recycling Korbel boxes each year around New Year's as this is the time of year when Korbel boxes are available in quantity from liquor stores.

I am posting the following photo story to show how to ideally resize them for the purpose of storing insulators.

This picture shows a trick I use to get clean fold lines on the cardboard. I place a yard stick on each side of where I want the fold line to be, press them together and then fold applying the pressure uniformly starting from the center.