> Have to say I'm wondering about hand-working these MCP1640
> DFN-8 packages though. MSOP8 is bad enough

Same as Olin, I've been doing some small packages and some TQFP PIC32s 
recently too (using drag soldering technique mostly, but also hot air, 
especially for smaller parts, SOT5-6 etc) and the hardest part I find is to 
align the chip properly before applying heat, the liquid flux certainly 
helps to keep the chip in place, it's a lot harder without it (small dab of 
glue apparantly helps with tiny components like 1206 caps/resistors, though 
I have not tried this myself). I found that you don't have to be *so* exact 
with alignment with the hot air, as the surface tension of the solder 
usually pulls the chip into place when it melts, like with reflow soldering 
(especially with larger packages). Solder paste can be used also instead of 
applying regular solder to the pads, this also has the nice effect of 
holding the component in place until heat is applied. For the drag 
soldering, I really like the Pace (angled) miniwave tip (fine pitch 
version - 
http://uk.farnell.com/pace/1121-0564-p5/tip-fine-pitch-miniwave-pk5/dp/3120740) - 
I didn't get the Pace iron, just ordered 5 replacement microwave tips and 
used them in my standard (non temperature sensing) iron - had no problems 
yet, although I really should get another half decent iron - last one died 
but as yet I seem to be doing fine without it. Plenty of tutorials out there 
on soldering/reworking the SMD stuff, I think the main thing is using plenty 
of flux, plus a bit of practice. My next project is to rig up a small reflow 
oven.. 


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