Many manufacturers do not have up-to-date drawings of the parts they make and some have never had part drawings of any kind.
Reverse engineering is defined by the Military Handbook MIL-HDBK-115 (ME) as the process of duplicating an item functionally and dimensionally by physically examining and measuring existing parts to develop the technical data (physical and material characteristics) required for competitive procurement.
Put more simply, reverse engineering is the process of creating a part drawing by measuring the existing part to determine dimensions and attainable tolerances, when no formal specifications exist. Tolerance development, often the most difficult aspect of the reverse engineering process, can be achieved only thorough a deep understanding of the part and its applications.
Reverse engineering is an ideal process to use in the following situations:
- A physical model of a product has been produced, but no drawings exist; such as when disaster destroys records or parts that come from an undocumented source.
- Drawings have been created, but working prototypes have been modified.
- Worn or broken parts that must be replaced, for which there are no drawings.
- A CAD system is introduced to the company, and all existing products must be uploaded into the system.
Reverse engineering is commonly used in redesign processes, as well as in the introduction of new products. In some cases, it may be easier to develop drawings of an existing product and modify them in a CAD system, than create new drawings from scratch. This is especially true for highly complex shapes and topographies.
Reverse engineering is easier today than ever before with a growing number of tools and technologies, easily integrated into existing CAD and CAM systems. Generally, the complexity of the part being reverse-engineered will dictate the type of equipment and software used.
Reverse engineering techniques can be as fundamental as straightforward manual measurement, or as advanced as cutting-edge laser and light digitized scanning systems. Handheld scanners can now digitize 3-D surfaces in real time, anywhere in the field that the part may be; inputting the information into remote CAD systems.
With all its applications, it's astonishing that reverse engineering is NOT a skill generally taught in technical college courses; even though it's an invaluable tool for design engineers. Why is this important? Because a great deal of practical learning about technologies, objects and systems can take place through reverse engineering. By analyzing the structure and function of a device or component, engineers can more easily improve upon previous designs.
Do you have any stories to tell about reverse engineering projects?