It's a pity I don't have a better pic of this axe. (And it's more than 1500km away now :S)
Well, it's inspired on the axe of Fyrkat, the inscription is taken from the Galdrarbok (a 16th century grimoire) and it is a spell to cause fear on the enemy.
The damascene is made by hand with burins, and the runes are made of copper.
It took me about an hour to an hour and a half each rune.
How do you put the cooper in? It does not "fall off" with some use?
There are few ways to take the copper out: with acid, with heat, or with a small chisel I'd say.
Unless the piece bends, the wire won't come off. That's why this technique is very well suited for rather small, sturdy pieces, like axes and knifes, and not so recommended for large and thin sheets that could bend, like in a helmet or a sword, for instance.