I cant think of very many gunmakers who learned their craft via apprenticeship, mention file making during their tool making phase (usually the first phase of the process is spending a lot of time in the machine shop and learning tool making, and to get out of that phase, your skills are judged by the master of the machine & toolmaking shop) of the apprenticeship. I talked about this with a friend of mine and he made no mention of ever making files. He did mention that file making was an entirely different animal and there were specialists for that....aka file making companies like Nicholson, Stanley, Grobet, Vallorbe, etc.
