Files & Rasps Buyer’s Guide
How to Work with Files & Rasps
Files and rasps are tools predominantly used for shaping and smoothing. While most of the people use both the terms synonymously, there are distinct differences between the two and the purposes it serves. Rasps are often used for aggressive and heavy work whereas files are preferred to give the material a refined finish. With practice, these tools can offer much more than power tools by reducing the time taken for sanding and shaping. Files and rasps come in different shapes, grades, features and usages. And to have an essential awareness on these grounds become essential while purchasing these tools.
Choosing the right files and rasps depend on the kind of material that is being worked with and the quality of finishing which is being expected. In most of the cases, files and rasps act as an intermediary step between rough sawing and finishing with sandpaper. These tools can be used on wood, plastic and metal and also be used to sharpen other tools, remove dust, and neaten metal and more.
Files produce a finer finish than rasps. They come in a variety of shapes but the most useful to woodworkers is probably the half-round, which has one flat surface and one opposing curved surface. Single-cut files have one set of parallel teeth cut into the surface. Double-cut files have two crisscrossing sets and produce a smoother finish. The grades of coarseness for files are the same as it is for rasps: bastard cut, second cut and smooth cut.
Rasps have individual teeth that are randomly placed to provide faster and rougher cut. Woodworking rasps are from 6 to 14 inches long and come in flat, round or half-round designs. They come in several degrees of coarseness. Wood rasps are the roughest, followed by cabinet rasps and patternmaker rasps. And within each of those three groups, there are different degrees of coarseness, from bastard cut (the roughest) to smooth cut (the smoothest). Teeth are spaced further apart on long rasps and closer enough on short ones. Short rasp will make a finer finish.
Keeping files and rasps clean is one of the key factors on ensuring the quality of work. These tools must be selected according to the right combinations of shape, size and grade for the project that one is hoping to work on. Working in only one direction with files and rasps will provide a higher quality finish for the work. It will also prevent the teeth of the tool from getting dull. Cleaning the files and rasps with wire brush or file cards can help them against clogging and keep them in working order. Rubbing chalk on the surface of the files and rasps can also prevent quick clogging.
Certain features to be always kept in mind are that files and rasps mostly come without handles and it would be ideal if a universal handle can be purchased in order to use different shapes of the tool within the single handle. Some files are designed with both round and flat surfaces and with two different ends, one of which is a file while the other is a rasp, making it a 4 in 1 tool. Diamond files which feature ground diamond particles make them apt tools for industrial applications and other hard surfaces. Smaller diamond files will work appropriately for glass, ceramic and other metals.