This paper is a reference for eliminating unnecessary weight that commonly occurs when the gage of metal parts exceeds nominal blueprint dimensions. This is accomplished at the Convair division of General Dynamics by the use of a closely controlled chemical process known as Dynamic Etching.

Recently completed studies indicate that over 85 percent of the gages on finished machined parts and sheet metal parts (except close tolerance sheet) are on the high side of the blueprint tolerance. This in the past has resulted in unnecessary and undesirable weight on aerospace vehicles. It is now economically feasible to re-uce or eliminate this excess weight by using Dynamic Etching as an additional finishing process.

This paper relates Convair's experiences with this process, based on both vendor and inhouse facilities. It shows:

1. What the economic and technical factors must be to make this a feasible approach to saving weight.

2. The organization and function responsibilities of participating departments.

3. Procedures required to assure proper control of the operation.

4. Some of the advantages and disadvantages of this process and awareness of some problems and pitfalls.

Dynamic Etching for weight control of finished parts can simplify manufacturing that would involve prohibitive costs in tooling and machining if done conventionally. The broad scope of its useful applications and its relative simplicity and cost (compared to conventional machining methods) provide the weight engineer, design engineer, and the manufacturing engineer answers to their traditional problems of weight control.