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▲ Flat File. When it comes to dressing edges and shaping metal, flat files work quickly.
The coarse, bastard-cut file is the workhorse. You'll use it to smooth rough edges and saw marks or to rough out the shapes of dovetails.
Next, you can progress to the second-cut file. It's great for smoothing a cut and refining tighter shapes. Finally, the smooth-cut flat file is for finish work. With it, you can get a crisp edge and smooth surface for metal joints.
Shaping Files. You'll also need some smaller files for the more intricate finish work, like making the double-dovetails used to join the sides and bed of the shoulder plane. The most commonly used of these smaller files is the triangular, or "three-square," smooth-cut file.
For work in tight spaces, needle files are the answer. They come in a variety of shapes and sizes. They're especially useful for detail work.
Barrette files are shaped like a knife blade with a flat cutting face and smooth beveled face. This is helpful for getting into tight spots where you don't want to mar the opposite face. I used a fine barrette file to clean up the mouth of the shoulder plane. They're also available in different cuts, listed as 00 through 6. The finest cut, 00, is used for extremely fine jewelry work. For most metal working, I find files in the 2-4 range work well.
Joining Metal Parts. Unlike working with wood, you won't need glue and clamps to assemble your metal projects. The strength of
A Triangle File. For shaping tight corners and angles, different sizes of triangular files work great.
these joints is usually mechanical, (although solder can be used to reinforce the joint). That's why careful shaping of interlocking pieces is so important. You don't want any gaps when joining metal. There is, however, a technique for closing gaps to secure a tight fit.
Peening, the process of hammering the mechanical joints of metal pieces together, expands metal and makes it "flow" into place. The tools required are a solid metal-working vise or anvil and a ball pein hammer, shown in the opening photo on page 40.
When you begin, it's helpful to keep in mind that metal is malleable. In other words, you can push and stretch the metal pieces together using carefully directed taps from the ball end of the hammer — don't pound the pieces like you would a nail.
Patience is the Key Technique. In the case of the shoulder plane, you'll be peening the brass dovetails into the steel sole. I found it easiest to work the angles back and forth, gradually learning to judge the amount of force necessary to coax the parts together.
As similar as metalworking is to woodworking, it will still take you a while to get the hang of it. Once you give it a try though, you'll be surprised at how quickly you can start using these basic techniques to add some variety to your woodworking projects. &
I prefer to use double-cut files (like those shown at right) for brass and mild steel. They have a second set of cutting ridges that runs diagonally to the first. I think of them like progressing through grits of sandpaper in a woodworking project.
Start with the coarse bastard cut. It will remove lots of metal in a hurry, so you'll need to be careful with brass. Progress to a second-cut file for smoothing and refining a shape. Finally, the smooth-cut file really excels at dressing edges and flat cutouts.
Shaping files allow you to refine tight corners, curves, and other shapes. I find that the round and triangular profiles come in handy on just about every metal project. These profiles are available in different sizes and cuts, all the way down to the very small needle files.
I like barrette files for work in tight spaces. They have a knife shape with cutting ridges on only one face to prevent scratching adjoining surfaces.
A Smooth Cut
m Keep your Files Clean. A file card is a necessity when shaping metal. Use it often to avoid loading up with fine metal filings.