Thanks. Weight is about 3,7kg and diameter 81,5cm. I have also shield made from aspen with birch burl boss, it haves about same diameter, maybe slightly more, and its not only rimmed, but also faced with leather.
Thanks. First i did cut the round disk from the steel. Then I heated the steel in forge and hammered it on the duct, so that the boss stretched to the hole. I had to heat it many times. When the boss was somehow shape I finished the hammering on the anvil.
I hope that you understand, my english is not too good