Hi all, can't find any real info on this online so thought I'd ask you guys=
..
The other day I tried my first "toaster oven" reflow, but instead of using
solder paste I had first hit the pads with a soldering iron and standard
63/37 solder wire, then plonked the components on top, as per a previous
"HASL reflow" thread.
I just set the oven to 250C and was closely watching both the solder
joints for signs of reflow and the oven thermometer I had in there.  I'm
thinking the thermometer was slow to react, or not reading the same heat
as the board was seeing, as around 220C (according to thermometer) the
board started warping, then rapidly released the foul-smelling evil black
goo.

So a few Q's:
- are the goo fumes poisonous?  The only reference I can find anywhere is
from SparkFun, who say it's the glue used to laminate the FR4 / copper,
and that it's really hard to get rid of the smell.  No mention of how
dangerous it is though.  i got out of there quick-smart and closed the
door, but took a few minutes to gather my wits and open garage doors and
get the board outside.  I hadn't been expecting anything like that, so
only had the nearby window wide open for ventilation.

- any tips on where I stuffed up?  I'm still not sure if the solder had
reflowed or not, it's hard to tell when the solder was shiny to begin with
rather than the grey paste state, and though the components seem stuck
down they don't particularly _look_ reflowed.

- reckon I should just lay down a line of paste using a syringe next time?
 Part of the board design needs a redesign, so it's not worth making a
stencil;  I just want to test a few of the circuit sections that "should"
be properly designed.

- I think next time I'll do a pre-heat and a pre-soak, my initial
temperature mapping seemed to indicate the heat-up of the oven from cold
was reasonably close to a good reflow profile, but obviously it ain't?=20
Oh, and I'll do it outside.

The victim:
http://img542.imageshack.us/img542/9649/f53k.jpg

Lee

--=20
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