Doable Renewables: 16 Alternative Energy Projects for Young Scientists

Doable Renewables: 16 Alternative Energy Projects for Young Scientists — page 7
IIIO The needle should be 15 inches long If your needle is a differ ent length adjust the width of the base The base should be 14 inch shorter than the length of the needle The rubber bands I used are 7 inches long cut apart and measured without stretch ing and 1 16 inch wide You can experiment with this but a band that is too strong or short may bend the needle But if the band is too loose it may not contract properly when heated Glue the three base pieces together in a stack The complete base assembly should appear as shown