I’m flattening glued panels of Douglas fir for the garden box. The timber arrived rough sawn and though nominally an inch it was anywhere between 7/8″ and 1 1/4″. Plenty to do!
I usually start with a small Jack plane with a heavily cambered iron: a scrub plane in essence. Then a toothing plane and finally a jointer. Because the fir is tearing out so horribly I’m only using the scrub to take off the highest points, then I’m doing the bulk of the work with the toothed low angle jack.
It seems to do magic…