measuring wheel metric

This is a metric measuring wheel . The gear with the arrow rotates once every 100 meters .The circumference of the wheel is half a meter and this needs to be printed to scale to work.You will need
1 m4 bolt 50mm or longer
1 m4 bolt 35mm or longer( flat countersunk head)- You can see the 3rd picture above why
2 m4 nuts and 2 washers .
The gear with the triangle rotates once every 10 meters but you cant really see it once the cover is on . I drew over the numbers with a marking pen to see