Random question, not much to do with Arduino specifically, but I am really sure I can get a quick, concise response to my question.
Looking at job postings, and one of them says that they want someone with good hand soldering and reworking skills.
I've googled PCB reworking and can't seem to find a simple definition. Can anyone give me one? What's it mean by 'reworking'? Any help appreciated. Thanks gang.
I THINK they are looking for a universal repairs man. PCBs that fail in production tests can be mended in many cases. However this is more typical for China made products...
Well, reworking was just a facet in the overall description. By reworking are we saying fixing crap soldering work and/or finding the (as an example) bad resistor and replacing it?
that is what I tend to think of
If you google for rework station you get all those hot air smt soldering stations and BGA rework. So I think they need someone who can operate those. Looks like a repair job.
Rework is removing and replacing components. This can be quite a skill depending on the package involved.
The most difficult rework involves BGA packages (Ball Grid Array). These are chips with hundreds and sometimes thousands of balls of solder on the underside normally on a 1mm pitch. Removing them is hard enough but then replacing them can be harder. You have to clean up the old sites, place it precisely and then apply heat from both sides with a precise temperature profile.
You have to clean up the old sites, place it precisely and then apply heat from both sides with a precise temperature profile.
Not to mention creating a custom stencil for the BGA pads, depositing just the right amount of solder paste on the pads (while maneuvering around the existing parts around it), prior to seating the BGA and reheating.
It would be a good idea to look into exactly what kind of rework skills are being sought. There is a big gap in skills necessary between removing/replacing resistors and working with BGA's as mentioned above.
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The Gadget Shield: accelerometer, RGB LED, IR transmit/receive, light sensor, potentiometers, pushbuttons
RuggedCircuits, generally we just reball the IC itself then place and reflow. Its much easier than placing paste down, especially when the surrounding area is populated with around 300 resistors/caps. I used to do a lot of rework(even had to remove potting compounds before I could remove the chips) but not so much now.
My favorite was always the Rap3G in the Nokia N73 which had 1 BGA stacked on top of another. We used InfraRed rework station to avoid blowing all the passives around.
That works only if the BGA balls are very planar. If they are irregular then you can easily have balls that don't make contact with pads. The paste ensures they all make contact. Of course, if you reball them yourself and ensure they are perfect, then problem solved 
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The Quick Shield: breakout all 28 pins to quick-connect terminals