Home Shop Machining/Equipment/Files

A Good File is a Wonderful Thing

There are a great many treatise on files available and not worth repeating here.

What an aspiring Home Shop Machinist needs to know is this:

• Files come in single or double cut. Single for finish, double for stock removal.
• They come in 'Fine' and 'Bastard', where the latter means a courser tooth pattern.
• They come in a great many shapes and sizes, useful for different tasks.
• Larger sizes generally have relatively courser tooth patterns.
• Some files have 'Safe Edges', which means the edge does not have teeth. They are useful when filing up to an edge.
• There is such a thing as a 'Lathe File' with teeth designed to cut better on the outside of circular work.

A Home Shop Machinist uses files to:

• Quickly shape a piece of metal. If there is not too much metal to remove, an experienced machinist can often shape a part faster with a file than it would take to set up a machine, properly secure the part, index it, and then make the cut.
• Improve the finish of a part. Properly used, a file can leave a very nice finish on metal.
• Improve the fit of a part. When high tolerances are required, it is common practice to leave a slight amount of material while lathing a part and then creep up on the final size with a file.
• Enlarge a hole. Oddly enough, a square file is the best choice to make round holes larger.