The Restoration of Erased Serial Identification Marks
| Author | P. B. Wilson |
| Published date | 01 July 1979 |
| Date | 01 July 1979 |
| DOI | http://doi.org/10.1177/0032258X7905200304 |
| Subject Matter | Article |
P. B. WILSON, B.A., C.Eng.,
M.I.M.
Home Office Forensic Science Laboratory, Wetherby
THE RESTORATION OF
ERASED SERIAL
IDENTIFICATION
MARKS
As any policeman knows, if an object can be moved, someone is
likely to steal it.
For
this reason an object of value is often marked
with a sequence of letters and numbers - an identification number,
which is unique to
that
one object, and which serves to identify the
item should it be found in the possession of a suspected thief or a
receiver of stolen goods. Unfortunately thieves are aware of this fact,
and
often take steps to remove the identification numbers from
stolen objects, in the hope
that
a recovered item can neither be
recognised,
nor
be proved to be stolen. Techniques are available for
the restoration of erased identification numbers on metallic articles,
and in this paper I willdescribe the means by which such numbers are
restored in Forensic Science Laboratories.
The methods commonly used for marking objects with
identification numbers are:-
(a) By indenting a series of numbers into a surface. Each single
symbol is produced by using a hardened steel punch, the face of
which bears a mirror image of the number, standing proud
from its surface. The indentation in the surface is produced by
striking the punch with a hammer.
Manufacturers often use a group of punches assembled
together in a block, the number being increased by one with
each succeeding component. Some numbers are coded to
indicate the place and date of manufacture of an article and, in
the case of
motor
vehicles, the model number of the vehicle.
Figure I shows an indented number, together with the face of
anumber "4" punch. The chassis and engine numbers of motor
cars and commercial vehicles,
and
motorcycle and bicycle
frame numbers are often indented in this way.
(b) By punching symbols into the reverse face of a thin sheet of
metal, often aluminium, so that they stand proud of the front
surface. Some
motor
vehicle engine and chassis number plates
are produced in this way. The plates are riveted to the vehicle
and can easily be removed or replaced by a thief.
(c) By engraving, that is by incising shallow grooves into a
surface using a sharp tool. This method is often used to provide
dedications or personal identification marks on items of
July 1979 233
To continue reading
Request your trial