I have 10 identical tables that I use to store costings for different customers

I set up a form with an incremental search field and a grid which displays
the record found.
The table name is x which I open as an alias (master)
This initial table is opened in the dataenvironment

I have a dropdown which lists the other identical tables.
In the valid I close master then open a new table as master.
When I close the table & open another table, the grid
goes completely blank. ( I issue thisform.grid1.refresh() )

If I say thisform.grid1.columns=10 and
thisform.grid1.recordsource="master"
the grid is recreated but not in the original format( header caption, width) and the doubleclick code is gone.

Any ideas on how to switch tables on the fly?

TIA