This is the case for a 7 magnet habach array that a friend requested. It requires seven cubic magnets 1cm x 1cm x 1cm with known poles. Please note that this can be a dangeous item to make and should not be played with. Habach arrays are amplified pseudo monopoles, creating  a strong magnetic force in one direction and a much weaker force in others. This gives them interesting properties but they make very strong magnets stronger and have a tendacy to wipe most electromagnetic substances, as well as crush hands. You'll also need some way of holding the ends on (I used glue but two hexagonal channels are present for non-magnetic bolts or screws (brass is okay)) as well as 7 10mm cube magnets with the poles marked.