Rubber Band Escapement
You can find a video about this here : https://youtu.be/4uL_IXx1_50
To finish it you will need 1 bearing 22mm by 8mm by 7mm and a thrust bearing 42mm by 25mm by 11mm. You will also need one rubber badn 5mm by 100mm long and a pice of rod 4mm thick by about 40-60cm long