Figure 3.35 A set of open-ended metric spanners

(Facom Tools Ltd )

Figure 3.36Straight and offset ring spanners

(Facom Tools Ltd )

Combination spanner

The combination spanner has an open-ended jaw at

one end and a ring on the other end. Both ends are

the same size. The combination is probably the

best choice of second set, for it complements either

open-ended spanner or ring spanner sets. Combination

spanner sets are available in AF in to in

and metric 3.2 mm to 32 mm (Figure 3.37).

Hand and power tools 107

Adjustable wrench

An adjustable wrench has one fixed jaw and one

movable jaw. The movable jaw is adjusted by

means of a worm wheel fitted in the handle, which

is meshed with teeth in the jaw. These wrenches

are useful because they are manufactured in a

range of sizes and each one can be adjusted to fit

many sizes of nuts (Figure 3.38).

Socket sets

In many situations a socket ratchet is much faster

and easier to use than an open-ended or ring spanner

because of its versatility in use, and in some body

repair applications it is absolutely essential. A basic

socket ratchet set consists of a ratchet, bar extensions,

a universal joint and a set of sockets (Figure 3.39).

Figure 3.37Combination and offset combination

spanners (Facom Tools Ltd )

Figure 3.38 A range of adjustable wrenches (Facom

Tools Ltd )

Figure 3.39Socket set (Facom Tools Ltd )

The barrel-shaped socket fits over and around a

given size of nut; inside it is shaped like the ring

spanner, having a set of teeth to grip the points

of the nut. Sockets are available with 6 pointed

teeth and 12 pointed teeth. A 6-point socket gives a

tight hold on a hex nut, minimizing slippage and

rounding of the nut’s points. The 12-point socket

does not have the holding power of the 6-point

socket, but its numerous positions maximize the

possible turning radius (Figure 3.40a).

The closed end of the socket has a square

hole into which the drive shaft of the ratchet fits

(Figure 3.40b). Socket sets can be purchased in , ,

and in drive sizes. The smaller drive sizes are

used for turning small fasteners, badges and trim

where little torque is required. The larger drive

sizes with the corresponding longer handles are

used where greater torque is needed. A body

repairer will need sets of , and in drive sockets.

The size of the individual sockets in a set

depends on the drive size of the set as well as the

number of sockets in the set. The socket size is

108Repair of Vehicle Bodies

the same as the face-to-face dimension of the bolt

it fits. A in set has sockets ranging from to in

(5 to 18 mm), whereas a in socket set has sockets

ranging from to in (13–40 mm).

Sockets are available not only in standard faceto-

face diameters, but also in various lengths or

bore depths. Normally the larger the socket size, the

deeper the well. Deep well sockets are made extra

long for reaching nuts or bolts in limited access

areas (Figure 3.40c).

Socket set accessories

Socket set accessories multiply the usefulness of

the socket set. A good socket set has a variety of

accessories such as:

Ratchet

Ratchet attachment

Extension bars

Speed brace

Long-hinged handle with universal joint

Sliding T-bar

Universal joint

Flexible spinner

Flexible extension

Coupler.

Screwdriver attachments

Screwdriver attachments are also available for use

with socket ratchets. These attachments are very

useful when a fastener cannot be loosened with

a regular screwdriver owing to lack of access

and space. The leverage that the ratchet handle

provides is often all it takes to move a stubborn

screw.

Screwdrivers

A variety of threaded fasteners used in the automotive

industries are assembled by the use of a

screwdriver. Each fastener requires a specific kind

of screwdriver, and a body repairer should have

several sizes of each type.

All screwdrivers, regardless of type, are designed

to have several things in common. The size of the

screwdriver is determined by the width or diameter

of the blade and the length of the shank. It is

important to select the blade tip accurately by

matching it to the size of the slot or the type of

fastener being used. The larger the handle, the

better the grip and the more torque it will generate

when turned.

Standard screwdriver (for slotted heads)

A slotted screw accepts a screwdriver with a

standard tip. The standard tip screwdriver is probably

the most common type used. The blade should

match the slot: an oversize screwdriver will not

(a)

(b)

(c)

Figure 3.40(a) Standard sockets (b) ratchet with

in drive (c) standard and deep well sockets (Facom

Tools Ltd )

Hand and power tools 109

reach the bottom of the slot and an undersize

screwdriver will float in the slot, and either condition

could result in damage to the tool and the

fastener.

Phillips screwdriver (for cross-heads)

Phillips screws have a four-pronged funnel-shaped

depression in the screw head, and are known as

cross-heads. The tip of the Phillips screwdriver has

four prongs that fit the four slots in the screw head.

The four surfaces enclose the screwdriver tip so

that there is less likelihood that the screwdriver

will slip off the fastener. The most useful set of

Phillips screwdrivers ranges from number 0 to

number 4.

Pozidriv screwdriver

This screwdriver is like a Phillips in that the head

is in the form of a cross, but the tip is flatter

and blunter. The square tip grips the screw head

and slips less than a Phillips screwdriver. Although

Pozidriv and Phillips look alike, they are not

interchangeable. The most useful set of Pozidriv

screwdrivers ranges from number 1 to number 4.

Torx screwdriver

The Torx fastener is used quite a lot on vehicle

bodies. The screwdriver has a six-pronged star

profile which provides greater turning power and

less slippage, and also ensures optimum pressure

to prevent the tool from slipping out of the fastener’s

head.

Speciality screwdrivers

These are normally in sets of screwdriver tips and

assorted drivers which are all interchangeable and

prove most useful in vehicle body repair work.

Toolchests

A cabinet-type toolchest as shown in Figure 3.41 is

standard equipment in most body shops. A portable

toolbox on top of the chest holds large hand and

power tools. A chest of drawers holds spanners,

sockets and all the necessary assembly tools. The

toolchest is on castors so that it can be conveniently

located in any working area of the body

shop.

Figure 3.42 shows a complete set of all assembly

tools.

3.18 Power tools used in body repair work

Choosing between pneumatic or electric power

tools has always been difficult because, while they

are designed to perform basically the same function,

the particular advantages and disadvantages

of each are so different.

Electric tools are simple to set up. They require

only a source of electric current, and so are suitable

for immediate use anywhere in the workshop.

The disadvantage is that because they have their

own power supply (the motor) incorporated, they

tend to be heavy and awkward for some jobs. Not

only that, but over-heavy use can wear the motor,

causing it to burn out.

Pneumatic tools, by contrast, are more complex.

Among the advantages they offer are the regulation

of air flow to suit the job, and the fact that they are

Figure 3.41Portable toolchest (Facom Tools Ltd )

110Repair of Vehicle Bodies

usually lighter, smaller and easier to handle. They

also require less maintenance than a comparable

electric tool. These factors can only be achieved,

however, if a high-performance air compressor

system is available. Moreover, it has long been

a disadvantage that, despite filters and regulators,

peneumatic tools can still blow oil, rust, dust and

other impurities into the atmosphere and on to the

work being treated.

Power tools play an important part in the

modern techniques used by the panel beater in the

repairing of crash damage to motor vehicles. Their

use reduces man hours to a minimum and they also

enable the operators to achieve better results than

those possible using hand tools. A wide range of

equipment is available to suit all types of crash

damage.

Section 3.19 to 3.25 describe the typical range of

power tools.

3.19 Air power chisel

This tool (Figure 3.43) is designed for the removal

of damaged panels so that essential stripping can

be carried out easily and quickly. It consists of a

chisel bit which is retained by a spring through one

end of a barrel, and a piston which moves to and

fro within the barrel, striking the end of the chisel

bit as it does so. The barrel must be kept dirt-free

to eliminate the possibility of undue wear by the

reciprocating movement of the chisel. A featheraction

trigger in the handle allows for variation in

the strength of the blow according to the amount of

pressure applied. To provide additional safety a

beehive or volute spring is fitted over the end of

the barrel to prevent the chisel leaving the tool

accidentally.

A wide range of special chisel bits is produced

for the power tool. Most of these are cutting chisels

of various sizes, used for general dismantling,

cutting rivets, nuts, bolts and the removal of spotwelded

sections. There is also a special thin-gauge

metal cutting chisel for use on panel work, and a

recessing tool which can be fitted on the end of the

chisel. The recessing tool can be used on the edges

of panels to form a lip or joggled section so that

one panel passes over the face of the other, forming

a flush finish which is ideal for spot-weld connections

and joints in panels.

3.20 Metal cutting shears and nibblers

Metal shears

These are usually electrically operated (Figure

3.44), but in some cases can be driven by compressed

air (Figure 3.45). They are designed to be

used in the hand with an on/off trigger control

built in the handle. The blade holding shoe is

designed in a spiral so that it parts the metal as it

cuts it. The machine is based on the principle of

shearing metal, and this is done by a pair of very

narrow blades, one of which is usually fixed

while the other moves to and fro from the fixed

blade at high speed. The blades have a very pronounced

angle or set to permit the blade to pierce

the sheet for internal cutting. The tool can be easily

turned when cutting owing to the narrow

width of the blades, and so can cut curved as well

as straight shapes. The shears are capable of

cutting sheet metal up to a maximum of 2 mm