摘要 |
In the plating of wire, particularly gold plating of wire for terminal pins, obtaining a high quality fixed gold plate is a problem. The invention provides for testing the wire prior to plating to detect surface irregularities which affect the quality of the plate. A test length of wire has a length of tape wrapped spirally around, with at least an edge portion in contact with the wire. The wire, and tape, is then twisted, in the direction of the spiral of the tape, in a direction to tighten the tape. The tape is then unwound and the number of particles of wire material which have separated from the wire at defects adhere to the tape is counted. For premium grade wire, less than 6 defects per foot is a standard. Commercial grade wire, between 50 and 150 defects per foot is normal.
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