10 types of traces of the tools of the crime

10 types of traces left behind by the tools of crime

[Axe hammer]:

The traces of depressions are square in outline and are formed by the top surface of the axe hammer.

[Screw blade type]:

The callout marks are trapezoidal and beveled in outline and were formed by prying with a screw blade type tool.

[Pincer, shear type]:

The whole genus line has peaked angle at the broken end, which is formed by the pincer, shear type of tool shearing.

[Knife, axe, etc.]:

The broken end has no peak angle and is sloped on one side, and is cut by a single-edged tool such as a knife or axe.

[Woodworker's drill]:

The bottom of the scar of the cutting hole has a spiral tip mark, which is cut by a woodworker's drill.

[Clamping twist drill]:

The bottom of the mark is tapered, must be formed by the clamping twist drill.

[Electric drill]:

Hole garden and hole wall smooth, is the electric drill cutting formation.

[Hand Drill]:

The cutting hole is not very garden and the wall of the hole has burrs, it is formed by hand drill.

[Scissors]:

Sharply angled indentation marks, caused by prying with scissors (sometimes in pairs).

[Pincers]:

Depressed marks consisting of a number of parallel lines that correspond to each other are formed by the gripping surface of a pincer tool.