Stuffing boards with pulled QFP chips

[Chuck Guzis]

On 04/01/2017 08:28 AM, Jon Elson wrote:
> On 03/31/2017 11:15 PM, Chuck Guzis via cctech wrote:
>> I use pretty much the same method, but start off with just a
>> binocular loupe and then finish with a stereo microscope for final
>> inspection.
> Oh, the trick for this is there are inspection microscopes with long 
> working distance that allow you plenty of room to get your hands and 
> tools under them.  Generally from about 4-6".  Then, it is a breeze
> to solder under the microscope.

My B&L Stereozoom allows a pretty generous space; I just don't like the
feel of doing soldering looking through two eyepieces. My 10 power
Optivisor doesn't get in the way and allows me to get the process
started easily.

As far as illumination, I find that a slightly  offset light source
under the microscope is more useful than the ring light.  You get a bit
of shadow with the offset source, which makes defects stand out a bit more.

BGA, on the other hand, is something that I haven't mastered--and I
doubt that I ever will, given the small size of some of the parts.

FWIW,
Chuck