A final thought. If you can influence the axial slack by fiddling with the coupling it means your thrust bearing MUST be slack and needs adjusting (preloading) correctly.
Phil
Originally Posted by philbur  You should preload the thrust bearing in order to remove slack. Not preload the coupling to remove slack in thrust bearing. Your motor bearings are probably currently taking the load, which is not good.
The thrust bearing is there to transfer load from the screw to the table without any axial slack. As I said previously the coupling should take no part in this. If you are using or "adjusting" the coupling to remove axial slack you are doing something wrong, period.
You need to workout how to preload the thrust bearing correctly.
Phil |