Actuate

Actuate is the first of Nubnubbud's automatically-adjusting drivers, made to overcome Operate's inefficiency. It begins a match by jumping violently, and ends the match spinning silently in the center. Choose your own spring and actuation time during construction! more weight in the tip means more extreme jumping, and a stronger spring reduces the time spent jumping! 

one pen or mechanical pencil spring not included (can be found in any common click pen or mechanical pencil. several different varieties suggested, preferably one under 15mm long and 4mm in diameter)
up to nine 4.5mm BB's not included (found at most sporting goods stores)
two m2x8 bolts not included (can be found at local hardware stores and online)
two m2 nuts not included (can be found at local hardware stores and online)
one driver spring  not included (https://us.misumi-ec.com/vona2/detail/110300268740/?HissuCode=UR13-15&PNSearch=UR13-15&searchFlow=results2type&KWSearch=UR13-15 or similar with fewer coils. maximum compressed height for easy function is 3.5mm. ideally, a custom spring will be used.)