Arfa Daily wrote:
"Michael A. Terrell" wrote in message
news
Arfa Daily wrote:
Sounds a bit like one of those late night cable programs "When Good
Snakes
Go Bad" :-)
We have discussed this topic on here a number of times, and one thing
that
usually comes up is how you get the stuff off. There's a switcher that I
do
which has a pair of small radial electrolytics 'folded over' and glued
down
on top of a whole bunch of surface mount components on the small drive /
control sub-board. Some of the components that are under the glue run
quite
hot - a zener for instance - and this has a double whammy effect on the
board in that first it turns the glue brown, which then becomes
conductive,
and then it also does a nice job of conducting the heat into the caps, to
ultimately **** those as well.
The glue gets right down between the pins of the PWM / driver IC amongst
other places, and is an absolute bitch to remove, without damaging
assorted
gnat's-bollock sized support components in the vicinity.
Well, today, quite by accident, I discovered that my favoured flux
removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening the
glue up. Not quite to the point of actually dissolving it, but enough
that
it can then be fairly easily picked off with a fine scalpel blade, and
then
scrubbed off with an old toothbrush, once you've got the thick of it off.
Is there a MSDS for that chemical?
Yes, several at the bottom of this page
http://uk.farnell.com/servisol/10001...0ml/dp/3821470
One little 'rider' that I should attach to this, as there seems to be more
than a little interest, is that the choice of toothbrush is quite important.
Cheapo clear coloured plastic supermarket jobs are a no-no with Deflux 160.
The bristles just fall out in very short order. I always use a 'Reach' brand
which is white plastic with rubber grips built into the handle. These are
completely untouched by the '160, and last until the bristles are worn down
to stubs. Actually, this one
http://www.boots.com/en/Reach-Interd...othbrush_1235/
I like the nylon brush in this set. It is like the old typewriter
brushes.
http://www.harborfreight.com/3-piece...set-40439.html