| If you could measure and chart 3 variables in my process, what would they be? | The boards that I produce are on panels that are 12up and 2x4 up. All boards are single sided paper base w/o plated thru holes. They are on scored panels that measure 7" x 17". | Bare boards packed 25 in a bundle are removed fron the cellophane wrapping, hand stamped and then IC's are installed by machine before proceeding to SMT. SMT operations consist of dispensing glue on the board with a needle type glue dispenser. This inline system feeds the board into the SMT machine. The SMT machine populates 420+ parts on the panel and then the panel proceeds to a conveyer where it stops until it is visually inspected. Once satisfied the inspector releases the board to the curing oven. The board is inverted, top side parts are installed on a progressive assembly line, the board is wave soldered, touched up and then tested on a bed of nails fixture. Current first pass yields are 85%
The others are right, you need to find out where your defects are coming from, but I wouldn't spend a lot of time with software packages or charts just yet. With 15% fallout, you must be doing a lot of rework on the failed boards, just ask your rework people what they are constantly reworking then figure out which process is causing them.
reply »