Page 73 - 05. Subyek Teknik Mesin - Automobile Mechanical and Electrical Systems Automotive Technology Vehicle Maintenance and Repair (Vehicle Maintenance Repr Nv2) by Tom Denton

1
58 Automobile mechanical and electrical systems

Figure 1.81 Repairs using a lathe. (Source: Wikimedia)

as a general description of hand skills usually used on a work bench or similar,
to construct an item that cannot be easily purchased – for example, a support
bracket for a modifi ed exhaust or a spacer plate to allow the connection of an
accessory of some type, such as additional lights.

Machinists usually work to very small tolerances, for example 0.1 mm, and
deal with all aspects of shaping and cutting. The operations most often carried
out by machinists are milling, drilling, turning and grinding. To carry out fi tting or
machining operations you should be familiar with:

measuring tools, e.g. a micrometer
●
hand tools, as found in a standard tool kit
●
machine tools, e.g. a bench drill
●
work holders, e.g. a vice
●

tool holders, e.g. the chuck of a drill
●
cutting tools, e.g. saws and fi les.
●
1.6.3 Filing

Filing is the process of removing material when manufacturing something; it
Key fact is used mostly for fi nishing operations. Filing can be used on a wide range

Files have forward-facing cutting of materials as a fi nishing process. Emery paper may be considered as a
teeth that cut best when pushed fi ling tool.
over the workpiece.
Files have forward-facing cutting teeth that cut best when pushed over the
workpiece. A process known as draw fi ling involves turning the fi le sideways and
pushing or pulling it across the work. This catches the teeth of the fi le sideways
and results in a very fi ne shaving action.

Files come in a wide variety of sizes, shapes, cuts and tooth confi gurations. The
most common cross-sections of a fi le are: fl at, round, half-round, triangular and
square. The cut of the fi le refers to how fi ne its teeth are. They are described,
from roughest to smoothest, as: rough, middle, bastard, second cut, smooth and
dead smooth. Figure 1.82 shows three common fi le cuts. Most fi les have teeth
on all faces, but some fl at fi les have teeth only on one face or edge, so that the
fi le can work against another edge without causing damage.