car tape
bennett built a car out of one of his many construction sets. he powered it with a tape measure. the spool was mounted in the car body. the end of the tape was secured to a box across the room. let go and zoooommm! off goes your tape measure racer. we clocked one run at 4 mph. it was easy. we knew the distance. it's a frikken tape measure after all. and we timed the seconds to get the speed. i never built one when i was a kid. go ben go.