Why in the world are you thinking that each termination requires an individual X-ray?
There is no reason for that.
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Jose A Rios
Sent: Tuesday, September 20, 2016 11:33 AM
To: [log in to unmask]
Subject: Re: [TN] J-STD-001 Space Addendum
6012 for example, does have different sampling allowances at different c=0 rates, depending on the attribute being evaluated.
Independent of the sampling rate, my original question was more 'what does the 001 Space Addendum require'. It says to examine hidden solder joints by X-Ray, not debating that, it just doesn’t state the extent. So if you have 300 hidden solder joints on a PWA, would 001 require you do to 300 X-rays….. per PWA. Thats what I was trying to gage. I should’ve also asked to respondents to state whether they are suppliers or users, to try to balance the responses in the absence of a clear direction.
Thank you all….
> On Sep 20, 2016, at 12:20 PM, Mattix, Dwight <[log in to unmask]> wrote:
>
> Tru dat.
>
> <runs off on tangential QE geekery>
> These days, does anybody actually apply dynamic changes to sampling rates based on changing levels of conformance? E.g. the old Mil-Std-105(?) sampling plan standard?
>
> -----Original Message-----
> From: Jose A Rios [mailto:[log in to unmask]]
> Sent: Tuesday, September 20, 2016 9:14 AM
> To: TechNet E-Mail Forum <[log in to unmask]>; Mattix, Dwight <[log in to unmask]>
> Subject: Re: [TN] J-STD-001 Space Addendum
>
> What I meant is that when placing replicate devices from the same lot across a pwb during assembly, the cleaning, the paste screening process, reflow process, etc is common to that pwb, hence lending itself to sampling.
>
>> On Sep 20, 2016, at 11:45 AM, Mattix, Dwight <[log in to unmask]> wrote:
>>
>> Re: "...the processing of the board is the same for the entire PWA??"
>>
>> Is that the only factor to ponder?
>> It would seem to be a first order effect to be sure.
>>
>> What about other inputs? E.g.
>> Variability in surface factors affecting wetting:
>> - solderable finish variance from pwb to pwb?
>> - Variability in surface cleanliness from pwb to pwb, different lots of pwbs
>> - variability in component lead's finish and wettability, different component lots
>>
>>
>> -----Original Message-----
>> From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D.
>> Sent: Tuesday, September 20, 2016 6:20 AM
>> To: [log in to unmask]
>> Subject: Re: [TN] J-STD-001 Space Addendum
>>
>> Agreed. The cost is neglible.
>>
>> -----Original Message-----
>> From: TechNet [mailto:[log in to unmask]] On Behalf Of John Burke
>> Sent: Monday, September 19, 2016 7:00 PM
>> To: [log in to unmask]
>> Subject: Re: [TN] J-STD-001 Space Addendum
>>
>> Xray every one of them.
>>
>> Best regards,
>>
>> John Burke
>>
>>
>>> On Sep 19, 2016, at 2:52 PM, Joey Rios <[log in to unmask]> wrote:
>>>
>>> Sections 7.5.14, 15 and 16 outlines inspection of hidden solder joints, invoking the use of X-Ray in the Space Addendum. The standard does not explicitly prescribe a sampling extent, so, if an assembly has dozens of the same device, like 50-100 say of such devices (such as a bottom termination component) on a single PWA, is the expectation (J-STD intent) that each of the replicate devices are inspected by X-Ray?? Is that what the industry practices, or is sampling commonly invoked, since the processing of the board is the same for the entire PWA??
>
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