Here are some of the problems (and my pet peeves) that can be found during a machine set-up. I have run into each of these many times over the years.
Wrong part value: This can usually be traced to a purchasing, incoming inspection, or kitting mistake. My favorite is when the part was put onto an old reel and the old numbers were left on. Always strip away old numbers or obliterate them.
Wrong Format: You programmed for tape and received the parts in tubes. Identifying specific formats for specific packages ahead of time for purchasing or whoever is supplying the parts is the best way to attack this. You may want all of your SOIC, TSOP and PLCC packages on tape. Or if you only do low volume you may always want them in tubes.
Tape with the leaders cut: Stockrooms are notorious for cutting the leader off tape to make counting of the material easier, or just cutting the tape into short pieces so they can issue exact counts. Of course then the tape needs to be stripped back or spliced to make it work on the feeder. In the past I have put up signs in the stock room- �Never Cut the Tape!�
Damaged Fine pitch parts in (or not in) Trays: Handling of FP parts in trays takes training for everyone who handles the parts. The machine operators and responsible engineers always seem to get the training, but not everyone else who handles the parts before and after. For moisture reasons the parts should stay in their original sealed package until the last possible moment before use. This will also have the desired affect of eliminating Pre-build damage. Of course there always seem to be parts left over, so they need to be properly secured in the correct (original) trays. My favorite is when FP parts are issued in bags.
Just a few issues. There are hundreds more.
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