So a wider process window of leaded paste (if you prefer, although it
is a two-dimensional thing, and I thought about the vertical,
conventionally temperature, axis) will not make hand soldering easier?
Besides, I would not call the reflow process hand soldering, even if
done in a manually controlled fashion with a hotplate or pizza oven.
But instead of discussing semantics, how about you two Pauls share
your combined century of experience to actually _help_ people?
ST
On Fri, Aug 22, 2014 at 10:26 PM, Jean-Paul Louis
louijp@...[Homebrew_PCBs] <
Homebrew_PCBs@yahoogroups.com> wrote:
> "Higher Process Window” is absolutely meaningless. The proper term should have been “wider process window” as the "process window” term is used in statical process control.
> And this is again not very relevant to hand soldering, where operator skill plays a huge role.
>
> Jean-Paul
> AC9GH
> over 40 years of Electronic Manufacturing Engineering experience
>
> On Aug 22, 2014, at 3:19 PM, palciatore@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
>
>> And that definition really clarifies things. I rest my case. Thanks!
>>
>>
>>
>> ---In Homebrew_PCBs@yahoogroups.com, <alienrelics@...> wrote :
>>
>> I have to disagree. I think it is important to learn the terms. If you don't know what someone means, don't be shy about Googling for it, or just asking. That's how you learn.
>> Process Window Index | Kicthermal.com
>>
>> Process Window Index | Kicthermal.com
>> PWI datasheet – click here PWI datasheet – A4 size – click here A Method for Quantifying Thermal Profile Performance The Process
>> View on kicthermal.com
>> Preview by Yahoo
>>
>>
>> "The Process Window Index
>> The Process Window Index (PWI™) is a quantifiable, reproducible, statistical measure of how well a profile performs relative to critical process limits. Every thermal profile is ranked on the basis of how it “fits” within the process window. The center of the process window is defined as zero, and the extreme edge of the process window as 99%. A PWI of 100% or more indicates that the profile will not process product within specification. A PWI of 99% indicates that the profile will process product within spec, but it is running at the very edge of the process window. A PWI of 70% indicates a profile is using 70% of the process spec.
>>
>> The PWI tells you exactly how much of your process window a given profile uses, and thus how robust that profile is. The lower the PWI, the better the profile. The thermal process can now be reliably measured, analyzed, compared and tracked with the same level of SPC and Quality Control available to other manufacturing processes."
>>
>> http://www.isixsigma.com/dictionary/process-window-index-pwi/
>>
>>
>> "Process Window Index (PWI)
>> A statistical measure that quantifies the robustness of a thermal process. PWI measures how well a process fits into a user-defined process limit known as the specification limit. PWI is used in the electronics manufacturing industry, particularly the soldering industry, where the scale and rankings were developed for various thermal processes."
>>
>> If I say eutectic solder, I may parenthetically define it. Or I may not. Either way, it is not an attempt to make anyone else feel like an outsider.
>>
>> Steve Greenfield AE7HD
>>
>>
>> ---In Homebrew_PCBs@yahoogroups.com, <palciatore@...> wrote :
>>
>> >Stefan,>Leaded paste has a higher process window than leadfree, so I
>> >would recommend that.
>> >
>> >When you say "higher process window", do you mean that there is more
>> >time to position the SMT before the solder hardens?
>>
>> When he says "higher process window" he means that HE is the more
>> knowledgeable, "IN" person in this conversation. He understands what
>> he is saying and he is using the "in" words to show this superiority.
>> If you, the outsider who dares to ask for clarification, he is going
>> to make you ask more questions to show your "ignorance".
>>
>>
>>
>>
>>
>
>
>
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