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N_Cook N_Cook is offline
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Default That brown glue stuff

Used for fixing otherwise floppy bits to boards.
Is it hygroscopic ? whatever the word is, but pulls dampness out of the air.
Beocenter 4000 from 1985 with the LC7815 (not V reg) electronic 2 pole 4 way
switch, internally locked into Aux only input, so disabling everything else.
0.7 inch pitch 28 pin DIP but now removed and replacement available.
Affected input was on one side of the IC and some of this ****ty brown stuff
on the other. But now removed , the 2 glued pins are almost corroded through
but not obvious before removing the IC, and have presumably conducted
moisture, capillary fashion, into the IC.
So will remove that glue and another dollop near another IC. Will hot-melt
glue go the same way after a qurter of a centuary.
Is it bulking filler in these glues that cause the problems ? I have used
talcum powder to bulk out on occassions but could that be problematic in
future , so a better choice?

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Diverse Devices, Southampton, England
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