That's great to see another one being built.
My latest thinking on the shields is that they were really thin. I've got the info somewhere, but they were only about 10mm thick at the rim and maybe twice that in the middle. The ideas seems to be, and how re-enacters fight, was to absorb the first blow, probably shatter, and then the warrior could attack and kill his asailant before they could recover from swinging their own weapon. 10mm at 1/60th or so would be less than 0.20 mm. Thin.
Diameter maybe 800mm, also small.
Really the only shields ever found related to a longboat were the ones at Gokstad, which were arranged in a circle around the ship if I recall. They all had the same paint job. No doubt the guy that was buried there's logo.