Case 174 ยท Public preview
Trapped Cleaning Liquid Can Concentrate Residue Exactly Where Contacts Meet
Small button switches exhibited intermittent or high-resistance contact behavior after field service.
Bench testingOptical microscopySEMEDSOpposing-contact comparison
What the evidence preview establishes
Residual gold-plating salts were deposited at the contact interfaces as trapped cleaning liquid evaporated from the capillary space between the mating surfaces.
Why this case matters
Closely spaced contacts can retain liquid after cleaning and concentrate dissolved salts during drying. Validate rinsing and drying inside capillary gaps, not only on exposed surfaces.
Full evidence reserved for MEMBER and STOREThe complete case includes the evidence sequence, four interpreted figures, alternative explanations, limitations, and practical application guidance.