Intro: DIY File Handles Without a Lathe
One of my favorite "free wood" locations had some mahogany (looking) sticks,
so I grabbed a few. They came in various colours and weights, and were part of some crating, probably originating in a country like Indonesia. Shown in picture #2.
My project was file handles, using only a plane, rasp, and sandpaper, or the handle blanks could be sawn into a rough shape using a table saw with a simple taper jig, as was done after making a few by just hand planning.
The ferrule is a length of steel tubing, from a chair leg, and was pressed on. The finish is wiped on boiled linseed oil. The octagonal shape helps to keep files from rolling off a work table. The taper helps to make a custom fit for your hand. The finished version is shown in picture #1.
The ferrules were fitted in two ways. The first, the handle end was shaped to a close fit with a file, then the ferrule was pushed on. I tried using a hole saw to shape the end, but found commercially sized saws produced a shape either too large or too small. So, I made a hole saw blade out of the tubing size I was using and that turned out to be the best solution. A few teeth were filed in the tubing's end and a mandrel was welded to the other end. The saw was turned by hand with a tap wrench that was a close fit to the mandrel. If no welding is available, you could drill through your newly made hole saw and turn it with a steel rod through the holes.
If you have large files to be fitted with handles, it is best to step drill the handles (three sizes of bits), which is the preferred method. If you just bore one size equal to the midpoint dimension of the tang, that works too, on the smaller sized files.
Picture #3 shows some earlier file handles made with a lathe. The example on the far LHS is simply a length of broom handle pushed on. It is from my father's collection and could easily be over a hundred years old