Setting default columns in Child Table for All Users

We have a few fields added to the Item Child Table in Quotation, SO, PO and all docs.
However we want to set default columns across the users. The problem we are facing is the columns get reset again and again and have to be manually changed for every user every time a new doc is created which is creating a lag in using the system. How can the same be set for all users at once. I tried the same setting the No. of Columns option in doctype customisation at the target fields but hasn’t helped.