Thanks for the help guys.

Big, I also realize the weight of the motor affects the effort, so I use the weight of the motor to help keep the blades position. I don’t notice any movement axially.

Jim, my saw does have a lock, but the buttons are worn or damaged because it will no longer lock the position. 
“I back past where I need it and then turn back in that direction to remove the backlash.”
I do the same thing and it’s a real pain in the butt. With so much slop, it’s easy to go past what I was aiming for and have to go back and try again. That’s actually why I decided I have to try to fix this. This might turn out to be something I won’t be able to solve.

.................. John D....................