Ready Steady Eddy

[EddyCurrent]

Been away for a few days, got back and now the PC graphics card has gone ! more expense.

Took the ball nut off like I mentioned earlier, emptied the contents into an old but clean washing up bowl I use for occasions like this.
The ball nut has 3 ball circuits and each ball measured about 3.15mm in diameter, maybe they are 1/8" inch ? anyway the number of balls that came out was 53 so right away you know there is something amiss. Before removing the ball nut the problem was that it felt like it was dragging and looking at grease patterns on the ball screw it looked like the centre ball circuit was stuck because the grease was being totally removed from the ball screw in those threads.

I watched this video on how to repack the ball nut and it was no problem putting it back together.
Linearmotionbearings C7 Ballnut Flipping and Repacking - YouTube

He explains in the video that 16 balls should be in each circuit which leaves a gap, I found that 17 balls left a similar gap so that's what I put back in and it's now nice and smooth running.

Edit: 10/12/2014 It was later confirmed that the correct number of balls for a 1605 or 1610 ball screw is 17 balls per circuit 51 total. (so that's good news for me !)

So the problem was too many balls in the ball nut so that they were jamming instead of rotating.