Isaiah Berlin's translation:

In a previous post, I mentioned Kant's phrase, which Isaiah Berlin translated as: "Out of the crooked timber of humanity no straight thing was ever made." This is a loose translation from Kant's original "Aus so krummem Holze, als woraus der Mensch gemacht ist, kann nichts ganz Gerades gezimmert werden"; Berlin seemed to have valued pithiness over accurate translation.

But now a copy of Berlin's book The Crooked Timber of Humanity: Chapters in the History of Ideas (1991) has just arrived, and it does seem that, as an epigraph (p. xi), Berlin does translate the Kant fairly accurately:

Out of timber so crooked as that from which man is made nothing entirely straight can be built.

This is in addition to the pithy translation, which is on p. 19. For an intermediate translation, see Against the Current: Essays in the History of Ideas (1980), p. 148: "Out of the crooked timber of humanity no straight thing can ever be made."