You may not consider a file a precision tool, but Henry T. Kramer has brought the badly hogged sole of a 22-in. jointer plane to within +-0.00125 in. of dead flat with only three files. In this article, he discusses 10 groups of “American Pattern” files, or about 170 files useful to woodworkers. He explains their history, how they differ, terms commonly used to describe files, and which ones are best to use on wood. The first thing you should do with a new file, he says, is put a handle on it. He explains how to use files and how to care for them and clean them. A side treatise by Dick Burrows talks about a catalog that describes files and rasps that meet the needs of every specialized trade and industry -- including slicing bread.

From Fine Woodworking #46