Obviously you have a problem with reading comprehension. You completely missed the reason that there was a motor addition at all. It had nothing to do with installing a variable speed motor. It so happened the the motor that I had sitting on the shelf was a powerful dc variable speed motor and the expensive mill motor was toast and I didn't want to spend a large amount of money just to spin the spindle. The motor could have been a fixed rpm motor, but I had the variable speed motor off of a treadmill, and it worked very well without spending a lot of money. In my view, you hurried through the story so that you could get to your real motivation, from reading some of your other posts about other people's projects, and that is to bash their endeavors. I can only guess that somehow you get a buzz out of that.
What is notable is that if you had read the reason for this motor addition, you wouldn't have made an issue of a VFD in the first place.