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From: Mike Tomlinson on 22 Aug 2008 02:36
In article <6h3gonFifgibU3(a)mid.individual.net>, Arno Wagner
<me(a)privacy.net> writes

>Oh, the chip will fall off. But with constrainst like
>"max 280C for 10 secs", no telling what thermal damage it
>will sustain in the hands of somebody that does not have
>a lot of experience with this and can do it fast.

Hence applying heat to the *back* of the board, not to the part
directly...

--
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From: chrisv on 22 Aug 2008 08:39
Squeeze wrote:

>Arno Wagner wrote in news:6h2g7fFi7ebeU2(a)mid.individual.net
>> Previously Mike Tomlinson <nospam(a)jasper.org.uk.invalid> wrote:
>>>
>>> Turn board over,
>>
>> part falls off cleanly.
>
>Yeah right.
>Parts are glued on to the board when it's populated with parts,
>before soldering, so they don't flow away when bath soldered.

Who says they were "bath soldered"? With a single-sided board,
there's no reason to glue components down.

From: Arno Wagner on 22 Aug 2008 12:04
Previously chrisv <chrisv(a)nospam.invalid> wrote:
> Squeeze wrote:

>>Arno Wagner wrote in news:6h2g7fFi7ebeU2(a)mid.individual.net
>>> Previously Mike Tomlinson <nospam(a)jasper.org.uk.invalid> wrote:
>>>>
>>>> Turn board over,
>>>
>>> part falls off cleanly.
>>
>>Yeah right.
>>Parts are glued on to the board when it's populated with parts,
>>before soldering, so they don't flow away when bath soldered.

> Who says they were "bath soldered"? With a single-sided board,
> there's no reason to glue components down.

Most are IR-Soldered today anf are initially clude into place
with the solder+flux paste. As they do not move by themselves
and melting the solder actually (weakly) pulls them into place
even more, I believe extra glueing is not used anymore in most
processes. Anyways I have not encounterd it for some time and
I just revcently modified a soundcard which involved de-soldering
some components (no chips though).

Arno
From: chrisv on 22 Aug 2008 13:25
Arno Wagner wrote:

>chrisv wrote:
>> Squeeze wrote:
>>>Yeah right.
>>>Parts are glued on to the board when it's populated with parts,
>>>before soldering, so they don't flow away when bath soldered.
>
>> Who says they were "bath soldered"? With a single-sided board,
>> there's no reason to glue components down.
>
>Most are IR-Soldered today anf are initially clude into place
>with the solder+flux paste.

What is "clude"?

Certainly it cannot be said that they are "glued" into place, even if
the paste is somewhat tacky.

>As they do not move by themselves
>and melting the solder actually (weakly) pulls them into place
>even more, I believe extra glueing is not used anymore in most
>processes.

Only for components on the bottom-side, if any, so they don't fall
off.

From: Arno Wagner on 22 Aug 2008 14:51
Previously chrisv <chrisv(a)nospam.invalid> wrote:
> Arno Wagner wrote:

>>chrisv wrote:
>>> Squeeze wrote:
>>>>Yeah right.
>>>>Parts are glued on to the board when it's populated with parts,
>>>>before soldering, so they don't flow away when bath soldered.
>>
>>> Who says they were "bath soldered"? With a single-sided board,
>>> there's no reason to glue components down.
>>
>>Most are IR-Soldered today anf are initially clude into place
>>with the solder+flux paste.

> What is "clude"?

> Certainly it cannot be said that they are "glued" into place, even if
> the paste is somewhat tacky.

They are actually glued into place with the solderin paste.
It is designed for that.

>>As they do not move by themselves
>>and melting the solder actually (weakly) pulls them into place
>>even more, I believe extra glueing is not used anymore in most
>>processes.

> Only for components on the bottom-side, if any, so they don't fall
> off.

Done on both sides. You do not solder them simultaneously and
with IR soldering, one side stays cool enough so soldering on the
other side is not an issue.

Arno

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