I just bought one... What did you use as a variable speed switch? Something like a Lutron Credenza Plug-In Dimmer? I don't know if the buffer is 2 or 3 prong and I'm having trouble finding a 3 prong dimmer that is not remote controlled.
But then I found an old Lutron floor dimmer switch in a drawer and it worked perfectly.
The black and decker is a 2 prong plug.
This is seriously an awesome tool / toy.
I’ve seen other massagers for like $700 that are basically the same thing rebranded.
Black & Decker WP900 Buffer
Lutron Credenza Dimmer TT-300