Application Shot Peening improves metal and weldment resistance to fatigue, stress corrosion cracking and galling. To provide this benefit, it is important that shot peen coverage be uniform and complete. A liquid tracer (Fluoro-Finder III) provides a coating which is removed at a rate proportional to peening coverage, providing visual feedback on the uniformity and completeness of peening coverage. Fluoro-Finder III, has a pigment which fluoresces under ultraviolet light making the determination of the degree or percentage of coverage quick, easy and foolproof. Use of this tracer eliminates the need for 200-percent coverage in order to be assured of complete peening. Method Description Clean the parts to be peened. Prepare a control specimen of the actual work piece. Coat this control specimen with Fluoro-Finder III by dipping, spraying or painting. Allow a few moments for the coating to dry. Check the control in a darkened area under a black (UV) light to insure that the area to be peened has been completely covered. The control is then shot peened using the correct intensity and parameters specified for complete coverage. After peening the control is re-examined under black light. Full coverage is indicated by complete removal of the tracer. Coverage of actual production pieces can be established using the same procedure for each part or on a statistical sampling basis. Often production peening is done under a black light. As the peeing progresses, it removes the Fluoro-Finder film, causing the glow to fade. Complete disappearance of the fluorescent glow indicates 100-percent coverage. Specifications Shelf Life: 2 years Boiling Point: 175.3o F (79.6o C) Flash Point: 20o F (-6.5o C) Percent Volatiles: 90 Specification Compliance MIL-S-13165 General Electric Aircraft Engines Specification D50TF9 Class A Interferences If the part is not properly pre-cleaned, tracer results may be erratic. When magnetic particle or dye penetrant inspection is required, parts should be inspected before peening. If these inspections are conducted after peening, they may not be able to locate discontinuities.