Hello: I built the 1500x1500 screw driven workbee. I have built the machine and assembled the electronics, however I am struggling with the tension in the Y plate nut blocks. The blocks spin freely when threaded onto the screw but when tightened down the tension is acting as a brake on one flank more than the other. In essence I expect that both Y screws should be at the same amount of tension and it has been difficult . Can anyone provide some advice on properly aligning the blocks so the screw turns as freely as possible? If there is supposed to be some tension, if so, how much? How tight should the blocks be screwed, seems the tighter the mount, the harder to turn.?