First of all thanks to Steve for the excellent clocks!!! I am a 3D-print beginner and my first project was the SP14. The clock is running reliable with 3 kg. I got a 3kg steel rod with 50 mm diameter. Unfortunately the rod did not fit into the weight shell provided by Steve. My first idea was to enlarge the extension but in that case the screw driver will be too short. Two or more extension might be possible but it doesn't look so nice. Finally, I created a new weight shell fitting exactly to my steel rod and since we are doing 3D-printing I avoided the screws by using a thread for upper and lower shell. In order to avoid supporting structures the treads have a chamfer which results in a small gap. Maybe, somebody has an idea for improvment.