[DMcMahon]

Some machines that are designed to operate horizontally can be noisy/very noisy when operated vertically, this can be because the flywheel/capstan shaft can easily move in the lateral direction when unit vertical (especially for machines where the top of the capstan shaft is not retained in an upper bearing), when operated horizontally the weight of the flywheel keeps the flywheel/capstan shaft in the lowered position (resting in lower bearing/on lower bearing pad) fairly stable position wise.

David