ball screw repair?

hello all,

i've bought an emco f1 a few weeks ago and i've spent some time to clean it and fix all kind of small problems. however, there is a major issue i don't know if i can fix by myself and i would appreciate expert advice.

it seemed that the machine has trouble with the X axis, rapid movement is not smooth and i had a feeling that something was wrong with the ball screw. i took it out and seen that from time to time it stucks at points and only after some playing back and forth with it i can get it to move. i understood that the two nuts were not alligned and after removing the screw i even saw that some balls fell out. to fix it i took the enitre thing apart and cleaned it a little and tried to put it together myself, however i get that exact same problem. i don't know if this is a problem with the ball screw or maybe i just need a professional to fit it all together.

i included a picture so you can see how the assembly looks like taken apart.

http://img441.imageshack.us/img441/6021/43540901qu4.jpg

This problem could be dirt inside the nut, not enough balls, dents in the nut or screw or if there are two nuts they may be to tight against each other.

You said you cleaned it " a little", to eliminate this question you have to completely disassemble it and really clean everything with grease cutting solvent and even compressed air, just don't loose any balls.

Inspect the screw with a 10X magnifying glass and look for small dents made by the balls, you shouldn't see any.

Count how many balls you hhave, and find out from the balls screw maker how many there should be, you don't want to be short more than a couple.

If you remove the screw from the nut, it is normal for the balls to fall out. But reassembling is very tricky and has to be done right, with ALL the balls. Search these forums, this topic has been covered in depth.

When the nut is assembled to the screw, does it turn smooth? The nut should turn smooth without stuttering, sticking, or tight spots. It should be the same from end to end, without it sticking or getting tight or loose.