Setting specific column width in Jaspersoft Studio

I am developing a report using Jaspersoft Studio. In the report some columns require only 3 Numbers (Unicode) and some columns 8 Numbers (Unicode).

I am trying to make the Column bigger in width which require long numbers so that it fits in one line and another one smaller in width that require short numbers (Only 3 numbers).

In Studio I tried to do with mouse draging but it automatically resize all other columns which is making it harder to fix the size for specific columns.

Any easier way to do this?

Here is the screenshot of JasperViewer:
_{(source: toile-libre.org)}

If it is a Table you can set the desired width directly in the Column, not in the cell or the cell component. I tried it and if I enter a number like 40 px directly into the Width field, everything seems to work out.