The side project is finished!!, I failed to reach sub 60 grams but 0.4 grams is not so much to talk about.
The final spacing is one thing left to do, I used 2.5mm thick carbon sheets , then the area around the teeths lathed down to 1.9mm.
The weight could be less by using 2mm sheets…
11-12T is in aluminum as the 11 and 12t in carbon would be very weak and breaking first.
Sending to a customer in USA who builds a very light road bike.
/Mattias the chief nailgunner.