I don't think the Fed Fund Rate is controlled by bonds, but by money supply. They remove dollars from circulation until the borrowing rate rises to a pre-define

I don't think the Fed Fund Rate is controlled by bonds, but by money supply. They remove dollars from circulation until the borrowing rate rises to a pre-defined rate (such as 2%). Banks don't typically borrow from the Fed as it's viewed as a sign of being unable to borrow from another bank. It's part of the reason the Big Banks were forced by the Fed to ask for a loan during the 2008 crisis, so smaller banks could ask for loans without looking weak.