I really should have included this entire handle making sequence earlier, on the Tuohipää Puukko, or stacked birch bark knife.

He compresses every few leaves, compresses even more, comes back and adds more, compresses more, heats in oven to soften the waxy bark, several more compressions, then lightly peens the pommel into place, then compresses and peens/compress/peens/compress until desired length finally reached.

This series is of the same knife handle, and I think everyone would agree the first shot shows mightly compressed bark compared to the 4 or so loose ones on top, and then the second shot with pommel lightly peened.

Then look at amount of compression (with more still to go) achieved during this in-progress shot.

A pretty solid handle, not always achieved with various makers of such handles, even with glue. I have seen some which were as riffling a deck of cards.