A few weeks ago, I already build a prototype for the escapement mechanism, as that was the part that I was most unsure of getting right. It worked out okay, I got it to run on a 13 g weight on a 10 cm lever arm, resulting in a torque of about 13 Nm on the escapement wheel. I calculated that to maintain that torque I would need a weight of about 10 kg to have the clock run for 24 h (which is or at lease was my self-set goal). So there is definitely room for improvement, but I see the first and biggest obstacle as overcome. Below you can see a video of the prototype in action: