Switch Board Burr
Designed by Jim Gooch, made by Eric Fuller, level 9.
(Pau Amerillo / Wenge / Bocote, 3 inches)
The pieces consist of a "block", two identical "rods" in symmetric
orientations, and two identical "plates" in symmetric orientations.
Orientate the puzzle as shown on the left below (the right rod will drop
down as shown if the puzzle is not too tight), exchange the plates by
passing them through each other,
then the right plate
(which was the left plate)
can be twisted
(in two ways)
(or without twisting it can be slid out together with the right rod).