Serial Number Restoration Techniques

PRINCIPLE OF RESTORATION - Serial numbers are usually stamped on a metal body or frame or on a plate with hard steel dies This results in the crystalline microstructure of the metal to get compressed strained When a suitable chemical reagent is applied the strained unstrained areas will dissolve the metal at different rate The unequal rate of dissolution of strained unstrained metal permits bringing out the original numbers. PURPOS E AND SCO.

Serial Number Restoration On Polymer Surfaces A Survey Of Recent Literature Sciencedirect

Since serial numbers together with the proof marks and wording related to the brand model caliber or manufacturer information can be regarded as unique in identifying and tracing the vehicles and firearms the restoration of these alphanumeric codes is vital in determining the items origin and owner.

Serial number restoration techniques. Infrared thermal imaging of metal surfaces provides thermal images sensitive to local differences in thermal conductivity of regions of plastic strain existing below a stamped number. Thus property can be returned to rightful owners or investigations can be initiated to curtb iradlle egal of contraband firearms. About 10 different reagents of which most of them are copper and iron containing less toxic less hazardous compounds were chosen for etching.

However many of these. Reconstruction technique may allow for reconstruction of even severely defaced serial numbers. The basis of serial number restoration is the detection of sub-surface microstructural change imparted by the marking tool.

Forensic scientists can use physical and chemical techniques to restore or enhance altered characters. Nondestructive restoration techniques include visual examination often with the aid of a low-powered microscope to establish. Restoration of Firearm Serial Numbers.

A serial number restoration involves the scientific techniques used for the retrieval recovery andor revisualization of the manufacturers identifier in cases where the serial number has been obliterated. One can utilize many methods that forensic scientists use to reveal the invisible. Is the serial number still visible after removal.

Law enforcement agencies submit firearms and other items to the BCA Forensic Science Services that have obliterated serial numbers serial numbers that have been ground filed or removed by other means. There are SEM imaging modes including forward scattered imaging FSI and. The handbook reports on the results of optimizing several restoration methods.

This course will consist of the following. The choice of restoration technique is determined by the type of metal involved the process by which the serial number was marked on the firearms barrel or receiver ie etching casting. When you apply the serial number with a device it presses into the metal to form a character.

The choice of restoration technique is determined by the type of metal involved the process by which the serial number was marked on the firearms barrel or receiver ie etching casting engraving or stamping and the method used to obliterate the serial number. In the case of a stamped serial number deformation of the metallic crystal structure remains below the surface even when the imprint is no longer visible. Nowadays many methods are available to restore the erased serial number.

This displaces the metal around the actual visible. This two-day Serial Number Restoration Techniques course will consist of lecture demonstrations and hands-on use of methodstechniques used to restorerecover serial numbers SN from firearms that have been obliterated and submitted to the forensic laboratory andor police agency. A number of techniques acid etching heat treating etc can partially or fully restore serial numbers.

Polishing the surface will help in visualizing the serial number. Only two of the seven serial number characters could be restored by his usual acid-etching techniques Klees said which meant police had to. Among several restoration techniques chemical etching is the most frequently used.

Serial Number Restoration Process The first step in the process of restoring the serial number is to polish the surface by using sand paper in progressively finer grits. Chemical etching is the most common and successful method for restoration of serial numbers on the metal surface. The restoration of obliterated serial numbers is a problem of common occurrence in the forensic field.

The primary purpose for restoring firearm serial numbers is to determine the prior owners or origin of the item from which the number has been recovered. Serial Numbers Restoration Techniques About Pete Striupaitis Peter Pete Striupaitis is a FirearmTool Mark Examiner TrainerEducator and Forensic Firearm and Toolmark Consultant. This project investigates the use of infrared thermal imaging as a non-destructive restoration technique for defaced stamped and laser engraved serial numbers.

Serial numbers were removed by grinding to a point just beyond obliteration. Chemical and electrolytic ultrasonic cavitation etching magnetic particle and heat treatment. All firearms manufactured post 1968 are required by law to have a serial number.

What many owners may not know is that even when they remove a serial number there may still be a way to see that number.

Serial Number