Hi Jeremy
Unfortunately I dont have "work in progress " shots ,my brother had borrowed my camera and I just got it back :-)
But you did guess correctly
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, lead foil was used around the borders as I needed to replicate the "press-studs" (for want of a better word
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)that attaches the cover to the mantlet.
I cut some thin strips of foil and marked these to correspond with the indentations on the existing mantlet , I then pressed a thin drill bit to create the "press-studs".
These strips where then attached with super glue then I built up thin layers of milliput blending this in with the lead foil with a wet paintbrush and at the same time tried to replicate folds and creases in the "canvas".
Ian