The novel massive spinor-helicity formalism of Arkani-Hamed, Huang and Huang provides an elegant way to calculate scattering amplitudes in quantum chromodynamics for arbitrary quark spin projections. In this talk I discuss the computation of two all-multiplicity families of tree-level QCD amplitudes with one massive quark pair and n-2 gluons. In these formulae the spin quantization axes can be tuned at will, which includes the case of the definite-helicity quark states.