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February 2016 • SMT Magazine 65 vibratory bowl feeder to present the pin to the pick-and-place machine. You see all those little pins in the video? You can see how they work their way up the bowl automatically, and then they work their way into this linear track. As you can see, the bowl feeder is designed to be mounted as any other component feeder on the pick-and-place machine—the same machine that's placing any other surface mount parts on the panel. During operation it appears that the bowl is rotating, but it's not; it's an optical illusion. Those pins are actually vibrating, up the ascending bowl track. The bowl isn't rotating at all. Goldman: Oh, perfect. Then they get placed. Borkes: You can see at the end they are auto- matically inserted into the solder paste. Then it will go through the oven and come out fin- ished. You've automated the insertion process. You've automated the soldering process. Every- thing is automated. Goldman: Who makes that equipment to line up those pins? Borkes: Many companies make the bowl feed- ers. Goldman: What is the process variation like? Borkes: With the pins lined up like soldiers in the bowl, you can achieve those 99.5%-plus yields. Once the process is developed and statis- tically capable, there is very little process varia- tion—i.e., a high Cpk index—so a small varia- tion in a relatively wide process window. Goldman: Without that manual hand soldering operation, which is huge cost reduction. Borkes: In fact, when you print the paste-in- hole during the same pass as the SMT compo- nents and use a bowl feeder to present the pins to a pick-and-place machine to permit automat- ic insertion, you cut the assembly labor content down by about 87% because it's all automated. You don't have the variability of a person with a soldering iron, soldering all these pins. Goldman: First of all, the operators doing the sol- dering want to try to be as fast as they can. Borkes: Exactly, then they've got to worry about the lining up of the pins, and they're holding them with tweezers. It's a lot less variation, and it's a lot more robust to work with an automa- tion process. However, again, this leads us back to the need for the school, to produce well trained, multi-functional engineers to develop and man- age this level of automation and the rest of the operation including procurement, scheduling, set-up, equipment maintenance, change-over, etc., in a product team arrangement. The tra- ditional organizational structure we have right now, what I call the Henry Ford division of la- bor model, in most cases uses very minimally skilled, very low-wage direct labor. Then, these people have to be supported by a hierarchal ar- rangement of departments whose indirect cost and overhead burden needs to be absorbed in the labor sell rate. This is what takes a $13.98 direct operator average wage on the floor and makes it a $32 labor sell rate. But there is an ironic thing that happens here: If your strategy to compete with low labor rate markets is to reduce labor content through exploiting automation, you're not going to have a lot of direct labor to absorb all that over- head. You're going to be forced to find a way Figure 6: Typical vibratory bowl feeders mounted on standard SMT placement machine. tHe JeFFersoN ProJect, Part 2