"Arfa Daily" wrote in
:



"William Sommerwerck" wrote in message
...
"N_Cook" wrote in message
...

Transistors , in this case 1-amp-continuous "size" whatever the SO
designation of that is.
If I've not used hot air then a scalpel tip or needle point, as used
here,
wedged under , soldering iron melt solder a touch leting the pins
relieve themselves away from the lands , repeat wedging/desolder
until fully free.
But this time the epoxy was more structural than just for placement.
I ended up breaking up the transistor body and the epoxy stayed
resolute. Any advice for next time? if relevant red colour and more
than a micro-dot
must have been under it as traces splurged out all around the body.

"In this case, the SMD was a one-ampere-capacity transistor.

"I wedged a scalpel tip (a needle point might work, too) under the
device. I
then touched a soldering iron to the pins, expecting that unsoldering
them would allow the chip to pop loose. Apparently, though, the epoxy
had been applied to keep the transistor forever in place, rather than
just long enough for the initial soldering. I ended up breaking the
transistor, while
the epoxy remained intact.

"Any advice for next time?"

I'm biting my tongue.


Because what you really want to say is ... ??





"if relevant red colour and more than a micro-dot must have been
under it as
traces splurged out all around the body."

I can only make the vaguest of guesses as to what Mr Cook was trying
to get
at.


Why are you having to guess at anything, William ? For once, I thought
it was quite clear that he was trying to remove the bloody thing from
the board to replace it with a new one. Obviously, you don't get
involved too much with surface mount reworks, as this is actually
quite a common problem.

Arfa



I'm still trying to figure out why epoxy was used to hold a SMD on the
board? thermal-conductive epoxy?

I also can't see epoxy having that tight a grip on the PCB,that it wouldn't
break loose before the SMD package broke. must be some damn good epoxy,wish
I knew who makes it and where to get it!

--
Jim Yanik
jyanik
at
localnet
dot com