Photos by Rob Brown; Illustration by Len Churchill
Files and rasps allow you to carefully remove small amounts of material with a freeform approach, mainly on concave and convex edges. These shaping tools help create and fair gentle curves, fine-tune edges and reduce the amount of sanding needed on some small, rough, 3D surfaces.
Rasps are more aggressive than files, and can shape wood fairly quickly. Files remove wood more slowly, and leave a smoother surface. They all come in a variety of lengths, cross section shapes and levels of coarseness. Used freehand, they are mainly used to shape wood into three dimensional shapes, like a cabriole leg or a chair back. Rasps are ‘stitched’, either by hand or by machine, to create the small individual cutting teeth. Hand stitched rasps are better, as they cut smoother and faster, but they are much more expensive. Wood rasps are the most aggressive general category of rasp, followed by cabinet rasps and patternmakers’ rasps. Within each of these categories are three levels: bastard (the roughest), second cut and smooth. When dealing with files the same levels are used to rate their level of coarseness. Shorter rasps and files tend to be less aggressive than longer versions.
Lengths: About 4″ to about 12″
Common Shapes: Flat, half round and round
Price: Rasps $15-$125; Files $5-$40
Don’t press too hard when using rasps and files. Letting the teeth do their job will allow for better cuts, and are less likely to clog the teeth.
Don’t allow rasps and files to come into contact with each other, as this will quickly dull the teeth.
A clogged rasp or file won’t work great. A file card is a specially designed brush that will remove wood dust from a rasp and file.
If your file or rasp didn’t come with a handle, add one to it. It will be much easier on your hands during use.
There are many variations of rasps and files. From different shapes to varying levels of coarseness, having a few available works out nicely.
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