Table 3-11. Magnetic Rubber Indication Codes.
A positive, definite indication. An A indication clearly contrasts with the
background replica material. It may apply to surface defects other than cracks.
All A indications are to be reported to engineering, along with orientation and
A fuzzy, unclear indication. A B indication can be due to improper inspection
technique or procedure, a dirty inspection area, or a subsurface defect. A B
indication is a temporary classification that has to be resolved to either an A
or a C indication.
The replica is clear of any defect indications.
A surface defect. This classification will be used only in those critical
inspections where the inspector is required to identify surface defects such as
corrosion pitting, tool marks, scratches, gouges, machine tears or chatter marks.
Rework inspection area and reinspect. For material removal limits refer to the appropriate
technical documentation. Remove only the material amount required to resolve the defect
Contact the appropriate engineering function if the material removal limits are reached before
the defect indication is resolved.
t. Surface finish visual inspection. After all A and B indications have been resolved (replicas from
the last inspection of the area are classified as C), the inspection area is ready for appropriate
personnel to evaluate the surface finish and configuration. The last replica may be examined in lieu of
the actual surface. If no additional rework is performed, the last inspection (paragraph v below) is not
u. Final inspection. The area will be inspected, if required by appropriate engineering directive, when
additional metal removal is performed to correct conditions noted in the surface finish visual inspection.
Post Inspection Procedures.
Cleaning solvent ML-C-38736 contains aromatic naphtha, ethyl acetate, methyl
ethyl ketone, and isopropyl alcohol. Cleaning solvent is flammable. Vapors may be
harmful. Use with adequate ventilation. Avoid contact with skin and eyes.
a. Demagnetize parts until the residual magnetism is less than two divisions on the magnetic field
b. Clean parts with cleaning solvent.
c. Restore finish in accordance with the appropriate engineering directives.
d. Reinstall parts removed in accordance with applicable technical manual.