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MAPP Gas: An Alternative to Oxyacetylene

NCJ Number
213440
Journal
Journal of Forensic Identification Volume: 56 Issue: 2 Dated: April 2006 Pages: 232-241
Author(s)
Brian E. Hogan; Darren R. Smith; Bradley R. Hall
Date Published
April 2006
Length
10 pages
Annotation
This experiment compared MAPP gas to oxyacetylene for use in the restoration of vehicle identification numbers.
Abstract
Because of the lower maximum temperature, heating capacity, and broader flame of MAPP gas compared with oxyacetylene, the heating of the metal surface is slower; however, this is an advantage. The slower heating of an engine block pad will decrease the chances of damaging the block and gaskets. Preliminary results from the current experiment show that MAPP gas--a stable, high-energy fuel--is a viable alternative to oxyacetylene when a heat treatment must be performed away from the vehicle examination facility. The relative ease of operation and light weight are advantages when a heat treatment must be applied to marine vessels or when vehicles or generators are located on properties that can only be accessed by foot. Another possible advantage of MAPP gas should also be explored. This is its use as a means of number recovery on chassis rails, vehicle panels, alloy engine blocks and casings, and firearms. This article provides background information on what is involved in the recovery of obliterated numbers stamped into metal. It then lists the materials used in the current experiment and describes in detail the procedure used in conducting the experiment. 9 figures, 1 table, and 6 references