Ok gurus got a question?

I dont claim to be a guru but I would say that the only cycle time you can control or be responsible for is your machine cycle time. Operator cycle time will vary and you cant control that.

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If you define cycle time as the time it takes to complete one board it is a useless number. What you need to know is the time it takes to complete one board and start the next board. This means first fiducial on first board to first fiducial on the next board, or first placement on the first board to the first placement on the next board. From this you can calculate capacity of the machine. If the operator has to carry a finished board halfway across the production floor to the next machine that is their cycle time. This does not mean the machine is out of spec because with a properly set-up factory this time could be reduced. Can the finished board be moved while the machine is builing the next board? Jerry

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I'm no guru, but I am among the best that my home state's gotta offer... :-)

Anywho.. a Production Manager's definition of cycle time is the time Production Planning schedules the stockroom to start picking materials for the work order, to the time the work order, in its entirety is shipped to the customer and closed out.

You, being from the Equipment side of the business, should only be concerned with your Equipment's cycle time...and...

....not the fact that the 10k resistors have a 2 week lead time because purchasing is trying to save $.0002 by buying them from a broker in Singapore, and when the resistors finally DO arrive, the stock room labels them incorrectly, thus screwing up the component verification system and inventory..after that's straightened out, we come to find out that Engineering has made a documentation error on their BOM, so the wrong revision product was built.... It's a different artwork, and Process Engineering gets blamed for not ordering the stencils for the job...that takes 3 more days...then..the machine programmer's grumpy, HE's got to respin his entire program because of Engineering's screw up....so..2 weeks and 3 days later...the work order is finally being built on the line, but then, the line technician is out sick with the flu, so debug takes a long time because the guy from the Proto area hasn't touched the machine in years.....it's new artwork so technically it's a proto build...now...Upper management catches wind of this that the work order is now 3 weeks late...he insists that we've built this product millions of times but doesn't know any details..all's he knows is that the boards "look the same" and there's no excuse why the line is struggling with a product we've built a million times...he hangs around the SMT line incessantly and then notices the "imbalance" between the 2 chipshooters..he forces the programmer to "re-optimize" the program, but then this introduces other problems..Finally 1.5 shifts later, the 1st piece gets inspected into a known good unit and now, the AOI program need to get done before the rest of the work order can be run... another shift later the work order is finally complete only to find out the ICT Engineer didn't read the ECO (he doesn't know how to use the new Electronic ECO system), and hasn't updated the fixture.....finally THIS gets done, but his pins are all bent and haven't been maintained..so he blames the new wave flux for his problems.... now..the poor Process Engineer has to dial down the fluxer settings to appease ICT..but then this introduces top-side wetting problems..so 3.5 weeks later...a work order that was perceived to take only 1 week, is 3.5 weeks late...Uppper Management has a meeting...and who else to blame but the "Slow Placement Machine" that didn't deliver the "promised" cycle time???

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