Depends on the spin-1/2 particle. You need something to "grab it with". Electrons "want to" stay aligned with magnetic fields[1]. Imagine two bar magnets, no

Depends on the spin-1/2 particle. You need something to "grab it with". Electrons "want to" stay aligned with magnetic fields[1]. Imagine two bar magnets, north to south: NNNSSS e- NNNSSS, with an electron in the middle. Spin the magnets around once. Tada! You've spun the electron too. The problem is that slight imperfections in the magnetic fields, as well as everything needed to move them greatly complicate what the actual effect will be on the electron. To really observe interference patterns, you'll need multiple paths, and many many measurements to tease out statistics. In addition to the fragility, moving stuff around for each measurement is infeasible for this reason. Continuous beams of electrons split and merged by magnet fields, with a continuous parameter on of the paths that can alter how much it is effected is needed. And at this point what's happening to the electrons look a lot more like math than like straightforward rotations. [1] Actually, they'll precess around the magnetic field axis, but if that axis starts close to the electron's axis, and is moved slowly, it will stay close.