Arfa Daily wrote in message
...




I tend to use a Biro pen, a hot air rework station (turned down to 100 deg
or so), a can of freezer, and the butt end of a bloody great screwdy. Oh
yes. And a lump hammer ... :-)

Seriously though, with normal leaded joints, I've never found it necessary
to use anything other than 'gentle' methods to pin a bad joint down to
within a square cm of board, which is what makes lead-free joint problems
so
incredibly frustrating. I get them all the time where you've only got to
look sideways at the board, and the joint will go bad, and yet no amount
of
provocation will bring it on when it's right, nor get it back when it's
wrong. And when you do eventually find it, the component is often hanging
out of the board - except you can't actually see that it is until you tug
on
it, or come to re-solder it, when the solder flies away from the component
leg to form a ring on the pad, leaving the leg looking as though it's
never
been soldered in its life ... And how many times do these lead-free bad
joint jobs bounce a couple of weeks later ? Can you imagine the
implications
if the rotten stuff ever does find its way into avionics and other
life-preserving areas ? New programme on Discovery ? "Aircrash
Investigation - The Lead-Free Years" ?

As to the Quad. It was from their "Lite" series. The owner's user guide
says
"03 - 05 Issue 1" inside its front cover so I'm guessing maybe 2005 ??
which
is before the 'official' lead-free introduction cut off point of June
2006,
but a number of manufacturers - notably Sony for instance - were
manufacturing with the stuff well in advance of that date. There is also a
note in the back cover about EC compliance requirements that it conforms
to,
but they are about EMC and voltage safety. No mention of lead-free.

I suppose it's possible that the thing was not built with lead-free, but
it
certainly looked and behaved like the stuff. Which brings us back to a
point
often made by Mr Cook. How do you tell for sure when the board isn't
categorically marked ?

I really don't know what alloy had been used on this. Only that it had
trouble melting on the end of my normal continuous-use
temperature-controlled bench iron, even when set at max. It did melt ok
with
the 140 watt Weller gun on it, but even with that, it only 'flowed' fairly
normally. Anyone who has ever used one of these beasts, will know that
under
normal circumstances, a small joint will be pretty much boiled on the tip
...

Arfa


I wonder if there is a "one-time" formulation of solder, low temp initial
use, then higher temp if reworked, or some sort of chemical de-eutectic
process over time.

The earliest PbF i've found was 2001 Yamaha unit