A reconfigurable multi-spindle apparatus for use with a machining device in a plurality of configurations across part families. In one embodiment, the reconfigurable multi-spindle apparatus may include at least two spindle head modules, a mechanism for transmitting power between the spindle head modules, and a mechanism for reconfigurably connecting the spindle head modules such that the multi-spindle apparatus is reconfigured from a first configuration to a second configuration across part families. An embodiment of a spindle head module may include two tool holders and a mechanism for adjusting the distance between the tool holders such that the multi-spindle apparatus is reconfigured within a part family.