The humble bastard file might not win any awards for beauty or innovation, but mine has been a workhorse over many years. Bastard files fall in between “Coarse” and “Second-Cut” or Finishing files on the coarseness scale. They are most commonly used when a moderate amount of material must be removed , and the appearance of tool marks on the workpiece is of secondary importance.
A bastard file can be used for any task where one wishes to remove metal without sparks or with greater control than is possible with an electric grinder. I used mine extensively in the building of my Jeep, especially when refinishing the axles. Most often though, I turn to it for sharpening axes, machetes, and lawnmower blades.
With all manner of electrified tools at our disposal, it is temptimg to pass on the hand tools. While I could use a hand-grinder, bench grinder, or belt sander to sharpen the above-mentioned utilitarian blades, it is usually faster to just clamp them in the vise and grab the file. (this often holds true when woodworking as well. You can often take 5x as long to set up a machine as simply grabbing a hand saw.)
I had my file out on Friday when I determined that my mower blades had passed the point of being “sub-optimal”. In fact it looked like I was mowing with a team of goats. It took on average 4 minutes to adequately resharpen each of the 2 edges on the pair of blades.
Visit EvenfallStudios for a wonderful and thorough guide to anything you ever wanted to know about files. Really an informative page.