CAUTION: Grey to Dark Arts following. If you don't want that shiny white robe soiled, you may want to go see what's on the Trideo...QUOTE (Sengir @ Sep 20 2013, 04:41 PM)

But doesn't all that struggling and thrashing get in the way of artistry a bit?
If one were limiting themselves to using purely crude physical tools yes it could, but there are a number of ways to restrain the more wild gyrations, from simple bonds/clamps up to an inhabiting spirit to control the main motor functions.
Note, more than a few Shadow type spirits will be amenable to this sort of participation, sharing the sensations with the working material, though always check your wardings/defenses as these sort of spirits are just as likely to try to drag you from being the artist into adding you to the art piece.
A dedicated spell designed for this sort of etching however, is guided by the will of the caster and the visualization of the artwork so changes in position/oritentation of the material in question itself does not hinder the crafting itself so long as one can maintain adequate focus/connection.
Some level of restraints as above are still used so as to avoid the subject from unnecessarily injuring itself (clawing madly at the leg from the sensations or trying to sever an artery as a means of release) or removing itself from the work area.
This spell by the way, is one of a series of spells to be used for a magical version of bone lacing for the purposes of lacing orichalcum onto the bones of an awakened being in a manner suitable for further runing and enchantment. Normal methods of lacing seem to degrade the potential of the orichalcum slightly from the process used and while it can be enchanted to a certain degree, but still not to it's true potential.
Sadly that particular procedure still has a number of issues of its own and best left for another day.