The detail which was missing for me from Bill Hammack's wonderful videos was how one might change the phase angle of a Fourier component from zero. I believe i

The detail which was missing for me from Bill Hammack's wonderful videos was how one might change the phase angle of a Fourier component from zero. I believe it's possible, at least within a discrete gear-tooth (the smallest gear component having the coarsest phase adjustment), by manipulating the "pinion gear". There's only so much one can stuff in a video; perhaps Bill has some mention of phase angles in his accompanying book.