A Tricky Tray was invented by Oswald Rae and described in his book The More You Watch (c. 1938). However, although it is a switching tray it is not the same as Ken Allen’s prop called Tricky Tray that was released 16 years later (C. 1954) and sold in two versions: the standard Tricky Tray (7″ x 12″) and the Tricky Tray Jr. (5.5″ x 7″).
Oswald Rae’s tray is significantly more complex than Ken Allen’s and for most circumstances I would use Ken’s. You can do similar effects with both, though Ken’s is more flexible and because it is so thin and plain it really does seem free from trickery.
Ken sold both of his trays with six pages of detailed instructions that features some really good ideas over and above the popular Bank Night effect.
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