Dan Maloney on the Hackaday blog:
To fight the shakes, you can do one of two things: remove the human, or improve the human. Unable to justify a pick and place robot for the former, [Tom] opted to build a quick hand support for surface-mount work, and the results are impressive considering it’s built entirely of scrap.
It’s just a three-piece arm with standard butt hinges for joints; mounted so the hinge pins are perpendicular to the work surface and fitted with a horizontal hand rest, it constrains movement to a plane above the PCB. A hole in the hand rest for a small vacuum tip allows [Tom] to pick up a part and place it on the board — he reports that the tackiness of the solder paste is enough to remove the SMD from the tip.