I like filing clean metal.
I file everything, cleaning up as well as shaping to suit me. Then hard-backed (file or wood)paper until the grit goes to 220 and then the shapes will only change very slowly from soft-backed sanding. I've gotten fairly decent service from all the 40 or 50 various cheapo needle files I've picked up over the years. Also, now and then I get a gooder one. And furthermore I've always a stash of saw chain sharping files as well as some small three-squares for hand saw sharpening.
The neat trick I just learned from bumping into the world of engraving is
blue putty. It's the stuff (not always blue) sold such that kids can hang posters on concrete block dorm room walls without using tape. What it's good for is "sucking" the filings from you file face or from your work of from any surface. Some engravers use it to pull chips from magnetized gravers (a revolting development it was the first time).
On a lark I started mashing my files into it for cleaning between X amount of strokes-depending on the file, as I was doing the recent cock fitment (from a casting of the other part-that was way different and demanded a LOT of filing) job on those pistols and found that it works great. I find it more effective than tapping the file in the smaller sizes.
Adapt, improvise, and glue wet/dry to wood.