That will definitely take care of having a variable speed buffer. I used a very similar setup on an old Shop Smith 10ER that I restored. I wanted a infinitely adjustable variable speed option that wasn't a mechanical pulley setup (yeah this thing is old)so I used the same type of solution with a different motor. I had a slight advantage as my dad was an electrician so all I had to do was tell him what I needed and it magically appeared.