Drilling Vice Problem

[Santacraig]

I have a Pen makers center drilling vice that I got from Woodcraft, and I am having trouble closing it on the blank.
It seems as though 1 side is hanging up,( I can't see any obstructions), and when I use my finger to turn the offending screw, it works ok. It's like one of the 2 screws is not being driven properly.
Does any one know if I can take this apart and fix it? It is item # 143609 on the Woodcraft site.:question:

 

[tim self]

Looking at the picture, check the two 7/16 nuts to see if one is to tight. It has a sweet spot between to tight and to loose causing slop. I have one and its been my problem before.

 

[wb7whi]

I know this does not contribute to the conversation but since I started drilling on the lathe I am most happy. I can control the drilling speed better and how fast I advance the drill and 98% of the blanks are right on for being true.

Of course if I was preping 100 blanks then I would go back to the drill press and the woodcraft vice.