Smitty Two wrote in
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In article ,
Ecnerwal wrote:
In article
,
wrote:
why is 63-37 eutectic solder not universally preferred?
Because sometimes you want mush.
Eutectic is either solid, or liquid.
Formulations off eutectic have a range of mushiness, which can be of
use.
And they have higher melting points, which can be of use in multipart
assemblies, where you might use 50-50, 60-40 and 63-37 to assemble and
solder a series of parts.
Interesting. I've not heard of this before. Do you speak from:
1 experience
2 rumor
3 speculation
Not wanting to be confrontational, just curious. Wikipedia lists melting
points as:
63/37: melts between 180-185°C
60/40: melts between 183-190°C
50/50: melts between 185-215°C
I'm not aware of any soldering process that is able to control
temperature so closely as to not melt one, while melting another of
those formulations. Can you elaborate?
When I worked as a process engineer for Sprague Electric Co, in the early
70's, making capacitors and resistors, we used 95/5 solder, I think it was
tin/lead with a small amount of silver, to assemble the capacitors and
resistors.
One reason for that choice was so that the parts would withstand normal
60/40 soldering when boards were assembled.
Like you, I have some doubts about the kind of close control that would be
needed to use mixes as close as the ones given.
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bz 73 de N5BZ k
please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.
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