I have came to the conclusion that ballnuts were made with the single purpose of making my Sunday afternoon a disaster.
Aftertrying to fit one to a ballscrew this afternoon it jammed part way on and wouldnt go any further. So I unscrewed it and reversed it to try from the other side. Same result, it jams part way on. So decided to take it off to have a look at it and found that some of the balls had gotten past the centre seals of the double ballnut and came out the centre. So I have about 20 balls lying on my bench at the moment and I`m not sure which race they came out of. I think the only way to be sure that it goes back together is to take all the balls out and start again. That should provide a few hours of fun.

Ian