I took it all apart this morning i can see wear on the z lead screw. So it was bent, as when i first built and tested it there was a bit of noise as the z axis went down with the kress attached, seemed ok going up but when lubed up it seemed to go away. The brass nut was tight, but trying the X lead screw in the brass nut for Z axis i can see some play as i move it up and down a bit. So i might aquire another one to be sure.