Dear forumites, armorers especially, I am trying to teach myself armor making but I run into problems. I set out to replicate two or three Norwegian shield bosses from the 9th and 10th centuries in the Museum of Cultural History in Oslo Norway, pictured on the VIKVERIR website. One is a 10th century simple dome with a saw-toothed flange, and I have a 10th c example that's a little more squat and with a slight indented waist that transitions into the flange by which it was nailed to the shield. The exampes are collected on the latest entry in my blog:

I made a flat buckler in 18 ga. with a domed shield boss and a rolled edge before this with instruction from armorer friends:

However, this shield boss project was my first attempt to hot-raise and I've done it mostly self-taught by imitating what I've seen other armorers do on their websites and in their videos. I am a total amateur. Fortunately I have access to a pretty nice workshop. I have a swage block, a big offset mushroom stake, a box of hammers, an oxyacetylene torch, and a workshop full of tools and machinery to work with. I've worked two 12 gaugue mild steel blanks into dome shapes, now the finesse work is what's getting hard. So far I've been mainly using the mushroom stake, but now that I have the curve of the dome and I want to start forming the flange with its distinctive waist I don't know what to do next. I've tried roughing the waist on the stake surface, but that doesn't seem to be as crisp or controllable as I want. It seems like I need an indented surface, but I don't know. The latest results are at the end of this facebook album of the project.;type=1

Basically, how does the armorer flange a Viking Norwegian shield boss in the style of the third photo set on my blog, the 10th century boss from Fossesholm next to the ax heads? I'm dying to know so that I can continue this experiment.