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solder fillet peeling update....

#25122

solder fillet peeling update.... | 9 July, 2003

Just when you think you're getting somewhere...

QA sent me a vendor response to our corrective action request. They stated that their normal process for this product includes an ultrasonic cleaning cycle of 20 MINUTES minimum. It might be 30, we're not sure from the language used. They going to reduce it to 10 (or 20) because they didn't see any cracks during testing at that soak time.

Klein Wassink references a maximum of 1.5 minutes, plus some other criteria for control of the process to make it doable. All I can say at this point is, if you're outsourcing, do your homework. Shortcuts will NOT save you money, or time.

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#25127

solder fillet peeling update.... | 10 July, 2003

Don't forget that you owe me a garnet pyroxenite, if you go over there to fix this problem.

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#25128

solder fillet peeling update.... | 10 July, 2003

I think the guys that write the checks are convinced that it's a service, not a problem. :P

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#25129

solder fillet peeling update.... | 10 July, 2003

Dang!!!! ;P

Hey, wait a minute!!! The BIG DOGS believe "it's a service, not a problem". Are you saying that they think that you're fortunate to get parts falling off of the boards? So there cracks are part of the value added? Whee!!

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#25144

solder fillet peeling update.... | 11 July, 2003

Component manufacturers recommend limits on the power and period of ultrasonic cleaning. Examples are: * PRECAUTIONS AND GUIDELINES MULTILAYER CERAMIC CAPACITORS: (9) Ultrasonic cleaning time shall be ten minutes maximum. When the power of ultrasonic cleaner is too high, the strength of terminations may drop. Therefore, carefully examine the cleaning conditions before use. [http://www.nippon.chemi-con.co.jp/pdf/catalog/ce-e1002e/ce-precaution-e-020924.pdf ] * Ultrasonic cleaning is permissible, the recommended conditions being 8 Watts/litre at 20-45 kHz, with a process cycle of 2 minutes vapor rinse, 2 minutes immersion in the ultrasonic solvent bath and finally 2 minutes vapor rinse. [http://www.avxcorp.com/docs/Catalogs/cguide.pdf ] * Cleaning (ultrasonic cleaning). To perform ultrasonic cleaning, observe the following conditions: Rinse bath capacity : Output of 20 watts per liter or less; Rinsing time: 5 min maximum; Do not vibrate the PCB/PWB directly; Excessive ultrasonic cleaning may lead to fatigue destruction of the lead wires. [ http://www.murata.com/catalog/c80/c80_02e.pdf ] * Table 8-1. Ultrasonic Cleaning - Power of Ultrasonic Cleaner: < 30 Watts per Liter; Ultrasonic Range: 39 KHz to 66 KHz; Cleaning Time: 3 Minutes per Cycle for 5 Cycles Not to Exceed a Total of 15 Minutes [ http://www.intel.com/design/packtech/ch_08.pdf ]

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MA/NY DDave

#25157

solder fillet peeling update.... | 14 July, 2003

Hi

So Steve,

I must have missed something from your last subject topic. "solder fillet peeling"

Are you saying you or they, Ultrasonic Clean for 20 to 30 minutes after soldering and that is suspected as causing the cracking at the top of the component joint.

YiEngr, MA/NY DDave

P.S. As an aside, years and years ago the company I was in discontinued Ultrasonic cleaning since the frequency was hitting a natural frequency of some packaged device.

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#25159

solder fillet peeling update.... | 14 July, 2003

Yes, they do the cleaning, we did the (apparently first) inspection and caught the problems. They tried a shorter cleaning cycle, witnessed no defects, and attributed the defects on the boards we had to their cleaning process. Now they just plan on using a shorter cleaning cycle. $50 says they won't do any cleanliness testing unless we tell them to and even then with some resistance.

I'd prefer they cease and desist and either change to nc or get a spray washer, but the decision isn't mine to make, apparently.

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#25161

solder fillet peeling update.... | 14 July, 2003

No cleanliness testing!!!! Yer just saying that to get a response, aren't you, Steve?

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MA/NY DDave

#25170

solder fillet peeling update.... | 15 July, 2003

Hi,

Although I grit my teeth it does sound like a normal process engineer or engineering situation. Here you are with knowledge and ways to get knowledge of best practices and No One listens.

----- Now I have a cleanliness testing joke (real story) of my own from years ago. I had three huge suppliers and everyone was up in arms because one of them was failing daily testing. All the Big Whigs were pressing on me with full weight. Then I asked for the results from the other two suppliers against all the weapons of mass destruction forces. WELL They stopped testing and supplying the results since they too were failing. -----

For your situation the best that you can do is to keep exposing the defect rates to your management in a "for your interest" type manner. That might work and it might not. GOOD LUCK.

YiEngr, MA/NY DDave

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#25171

solder fillet peeling update.... | 15 July, 2003

It is an interesting situation....one that merits as much business philosophy analysis as technical analysis.

I'll be getting my official 60 day notice today. Any criticism about our overseas suppliers (that were selected by sr. management w/o input from technical people) has been responded to with denial and accusations that we're being overly critical.

At what point does a guy just throw up his hands and say "this is your bed, and you are welcome to lie in it, and I'm done telling you repeatedly that it's positioned over a volcano"?

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#25190

solder fillet peeling update.... | 16 July, 2003

Well, technically speaking I was simply stating my opinion, but in retrospect (and after reading your response) I'm glad it had the affect it did. I needed the laugh. ;)

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#25191

solder fillet peeling update.... | 16 July, 2003

Massa be settin' yu freee, boi.

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#25204

solder fillet peeling update.... | 17 July, 2003

Word.

WARN + NAFTA = (outplacement assistance + extended unemployment benefits) * Federal retraining $$ = outta here

It's been fun. It's been a tremendous learning experience. It's even been lucrative, to some degree. But, it's also been tapped out, at least around here.

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iman

#25224

solder fillet peeling update.... | 18 July, 2003

I can relate to your situation. You are not alone... good luck!

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