D,
I usually post only on the Antique Machinery Forum but happened to look here tonight .
I see I’m a bit late since it sounds like you got it fixed while I was typing.
It has been a while since I had a unisaw apart and there are a few variations but this might give you an idea If cleaning the worm as suggested by others doesn’t do the trick
The 2 small pins that get forced out by your lock knob my be sticking and holding too tightly and may get jammed in and not release when you unscrew the knob.
http://www.sawcenter.com/pointer&bracket.htm
As I recall they expand into the pointer bracket which is come kind of die cast aluminum or other alloy .
I have seen those get scored and galled that could cause the hand wheel to be hard to turn
You might try squirting some WD40 or similar liquid in the lock screw hole and into the pointer bracket and see if that doesn’t help free it up .
You should hit the worm and gear and anything else that moves with some lubricating liquid as well and clean it up later.
You may need to get a new pointer bracket if it is worn badly .
I found the link above here
http://www.sawcenter.com/unisawparts.htm
Look For
Replacement pointer bracket
click here to see the how to assemble
Main Page
http://www.sawcenter.com/
Thanks to OWM site for the link I found here
Delta Manufacturing Co. - History | VintageMachinery.org
Good Luck .
Regards,
Jim