Fettling is a word that is used in several different senses. Most of the uses of the word relate to cleaning, polishing, and maintaining systems so that they will be functional or will remain functional. The word itself is derived from a root word referring to “condition,” as seen in the phrase “in fine fettle,” which is meant to convey that the person or object being described is in good condition, shape, or health.
In the railroad industry, this term is used to describe routine maintenance performed on tracks. It includes confirming that the rails are aligned properly, checking drainage systems, replacing ties if necessary, and conducting other tasks which will keep the tracks in good condition. It is important for this maintenance to be performed on a regular basis since a wide variety of situations can cause damage to the tracks, and this can result in damage to trains passing over the tracks, most spectacularly in the case of a derailment.
Track fettling is usually accomplished with the assistance of a small handcar or truck specially fitted to roll on the tracks, which allows track workers to carry tools and replacement parts as they traverse the track to inspect it. This is done in constant rotation to make sure that all of the track is seen at some point or another.
In metalworking, the term refers both to lining a chamber into which metal is poured for molding, and to cleaning metal after molding to remove the materials used for lining. This can include cutting, sandblasting, and polishing, all of which are performed to bring the metal to high luster and an even texture so that it will be functional and visually appealing. For cast parts, this action is very important to ensure that the parts will work properly.
People can also see this word used in ceramics, to refer to trimming, finishing, and polishing pieces. A fettling knife can be used to cut in patterns and details, and also to trim away excess clay, to remove marks left by molds and stands, and so forth. This action is performed so that the finished piece will be even and attractive, whether it is a ceramic bowl or a molded insulator for electronics.
In some regions of the word, this is a slang term used in general to talk about maintenance, tidying up, and making something presentable or functional. People may suggest that objects in disrepair just need “a bit of fettling” to be set to rights.