MIL-HDBK-115 Us Army Reverse Engineering Handbook Guidelines And ProceduresThis HANDBOOK, which provides the guidelines and procedures for performing reverse engineering, was created using current applicable laws and knowledge gained during a trial program from July 1985 to April 1987, and is based on experiences obtained from military and industry participants. This handbook is for guidance only and cannot be cited as a requirement.

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MIL-HDBK-115B(ARMY)

previously may be cross-sectioned and cut away if necessary to establish the dimensional data.

5.21.2 Considerations. The following should be considered when performing the dimensional analysis:

a. Bearing housings and shaft fits should be noted. When they are not in accordance with standard recommended practices in the bearing manufacturer's catalog, additional bearing seats and tolerances should be reviewed and investigated. The variation could be a manufacturing error or done deliberately for some engineering purpose.

b. Assumptions concerning screw threads should be avoided since manufacturers often produce unique threads to prevent others from copying them or substituting standard threaded parts. The pitch diameter should be measured and compared to the classes provided in Federal Standard H28/18.

c. All clearances should be measured and noted to assist in the tolerancing of individual parts. These should include, but are not limited to:

(1) Lateral movement,

(2) Backlash (gears and splines), (3) Torque,

(4) Operating loads (i.e., handles), and

(5) Keyway clearances.

d. Welded joints should be cross-sectioned to determine the depth of penetration and the preparation treatment which may have to be performed and the length and size of fillets and bevels used.

e. When parts have features that appear to be of no useful function for the item's intended use, consideration should be given to the manufacturing processes involved. A hole or protrusion could have been designed to facilitate the manufacturer's requirements. Such features should be noted. When the final drawing is prepared, those features should be indicated as optional for manufacturing purposes.

f. In many cases, manufacturing methods, such as punched parts, injection molded, or investment cast parts, indicate dimensional requirements.

(1) Normally, items that are sheared or punched do not require a good surface finish on the sheared edge. However, in some cases, the

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