Hi Bill! Just one short addition to add to Doug's comments (give the guy a
Mt. Dew and step out of the way!). One other perspective to consider with
regards to the J1C  "materials re-qualification" issue is to think not that
the specification is forcing you to requal but is questioning "do you have
the technical rationale/data basis for making a material change?". When we
change materials in our processes at Rockwell Collins we always do some
type of re-qualification - either a technical comparison on paper, a short
T-test of material process parameters or a full blown DOE. These efforts
are documented in internal reports and are used to demonstrate to both
internal and external customers that the material choices and process
parameter settings were selected not by random or by whim but chosen
deliberately as part of consistent management of a materials system. And we
have found that the internal reports are referenced/used repeatably  over a
multiyear period - not just once and forgotten. Should you/do you have to
conduct a full blown DOE requal per JC1 for every material change? -
depends on your customers but I am willing to bet that if you can
demonstrate/show them a logical path of why materials/process changes were
made then you will have fewer full blown requal's to conduct and can focus
on other process improvements. Good Luck.

Dave Hillman
Rockwelln Collins
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"Kasprzak, Bill (sys) USX" <[log in to unmask]>@ipc.org> on 08/21/2002
01:08:08 PM

Please respond to "TechNet E-Mail Forum." <[log in to unmask]>; Please respond
       to "Kasprzak, Bill (sys) USX" <[log in to unmask]>

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Subject:    [TN] J-Std-001C Qualification


'netters:

I have a general question for those folks out there who do J-Std-001C,
class
3 work. We use fluxes that are stronger than the "allowed" L0 or L1
activity
levels. Because of this I had to "qualify" our process per Appendix B of
the
J-Std-001C. This according to J-Std-001C, paragraph 4.2b. The cost of doing
this test, including materials, labor and whatever is approximately $7000.

Now I have a couple of questions...

1) If one of the solder pastes that you qualified is no longer available,
do
you have to do a re-qualification if the manufacturer of the paste suggests
a new material? (This implies a material change)

2) If you swap out a spray fluxer for a foam fluxer or apply flux with a
different method at the wavesolder machine, do you have to do a
re-qualification? (This implies a process change)

I suspect the answer to both questions is yes. With the number of possible
changes within a soldering process, it seems inevitable that process
qualification and re-qualification could happen on a regular basis due to
circumstances beyond your control.

So are the class 3 guys out there either doing regular qualification
testing
or are you all using L0 or L1 (no clean/Rosin) fluxes.

Is there anyone out there who participated in the writing of this section
who can shed some light on the thought process behind this section of the
spec.

Thanks to all respondents.

Bill Kasprzak
Moog Inc. Manufacturing Engineering, Electronics

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