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Ok gurus got a question?

Views: 1658

#45782

Ok gurus got a question? | 29 November, 2006

Have something that should be standard but never is.

Cycle time.

Long story short. Customer buys system. 8 months later customer says system isn't working as should. Go onsite and find customers application is causing huge maintenance problems. Solve issue with daily maintenance.

Customer then wants to decrease "Cycle" time. Engineering and software dept come up with custom application. (customer approved new hardware before it shipped with onsite visit). Customer has given us PO for upgrade.

So basically I go onsite install upgrade, get everything working and leave. System is working in accordance to customers specs (cycle time) however now he decides to include in his cycle time how long it takes his operators to load/unload/put on other system as "cycle" time.

Now obviously everybody will say what exactly was agreed too? We are a small company and contracts are not usually gone over by a lawyer before everybody signs up so "cycle" time was agreed upon.

Basically when you determine "cycle" time is it time spent in the machine or is it time from machine to machine, which involves human intervention?

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aj

#45803

Ok gurus got a question? | 30 November, 2006

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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non guru

#45806

Ok gurus got a question? | 30 November, 2006

Absolutely, you should be held accountable for untrained operators, slow operators, bathroom breaks and any other human intervention! Are weekends affecting cycle time as well? You have a "tough" customer you're dealing with.

Good luck

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#45809

Ok gurus got a question? | 30 November, 2006

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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SWAG

#45810

Ok gurus got a question? | 30 November, 2006

Cycle time is one thing, "operating factor" is another. Set-up and tear-down should be seperate from cycle time as well.

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CK the Flip

#45814

Ok gurus got a question? | 30 November, 2006

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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#45815

Ok gurus got a question? | 30 November, 2006

I like this definition the best. After years of sales of pick and place and other, this is always still a topic of discussion. If your customer's cycle time involves building a board in two different machines, then I would suggest measuring and adding the two different cycle times. FIRST MACHINE: From the time the machine sees fiducial one on one board until it sees fid1 on the next board that is staged and ready. Q up more than one board, make same time measurement on second machine. I think this would be hard to argue with.

Also, if you could Q up more than a couple of boards on the first machine first, and then keep boards moving, how many boards could they build in some number of minutes (make sure feeders don't go empty during this test).

Sell them a conveyor...or two... http://ietechnology.net/ietechnology.net/conveyorsystems.asp ......hey, I've got to try to sell something, advise is not really free...

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#45816

Ok gurus got a question? | 30 November, 2006

I have the feeling FishingFool's situation or dilemma is not a PCB Assembly related application......or at least it's not a component placement related application with auto board loading and fiducial recognition. That would be too easy to figure out now wouldn't it?

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#45821

Ok gurus got a question? | 30 November, 2006

Wow, Sigapore has resistors at $0.0002 off?!?!?!?

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aj

#45906

Ok gurus got a question? | 4 December, 2006

It all sounds so familiar !!!!

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