Another faulty adage
Today, "Crooked Timber" is a popular blog.
Like many current cliches, the term “crooked timber” reflects an obsolete technology. In Kant’s time, lumber was normally hewn ad hoc with an adze or other instrument.
Beginning in the 1840s, however, lumber mills became the standard source for wood. They produced regular planks, allowing for what is termed balloon-framing construction. This technique produces the wooden skeleton of uniform frames that we normally see as a house is going up.
Perhaps the metaphor is valid about crooked timber. Yet there is no need actually to make use of crooked timber, unless you think it looks picturesque. Instead, go to a lumber yard. Out of this timber, carefully hewn according to exacting standards, lots of straight things have been made.