The line-width selector (Figure 6.22) allows you to specify the width of lines painted by the Line tool, the Arc tool, and the various shape tools (Figure 6.23).
Choose Edit > Preferences > Paint (Windows) or Director > Preferences > Paint (Mac).
or
Double-click the Other Line Width button in the Paint Tool palette. (It's the only option in the line-width selector that's displayed as text.)
The Paint window Preferences dialog box opens.
Use the "Other" Line Width slider or the adjacent arrows to set the line width (Figure 6.24).
Click OK.
The Other Line Width button on the Paint Tool palette displays the line width you selected.