Got new 'low' cost wheels with noticeable rattling in both of them. Thought cartridge bearings had an excessive play. Turns out there is some play between bearing inner ring and axle.
Lock nuts were quite tight. After undoing the non-drive side nuts and and tightening them finger tight the play disappears. After tightening the quick release skewer the wheel seems like it's not turning freely enough.
Then after tightening the round nut against the lock nut when the skewer is tightened everything seems fine, but after removing the wheel lock nut is completely loose. Could it be due to loose low quality threads on round nut and lock nut?
Don't have much experience with cartridge bearing hubs as I got these due to partially cracked rims on old wheels and was tired of adjusting the cup and cone type ones.
Probably some of them have bearing sleeves like these (the picture is unintelligible).
Regarding to bearing preload, don't know why spring loaded bearings like these aren't used in bicycle hubs.