Symbolising A Shared Boundary

[MarkYoung]

Hi,
I have numerous polygons which share the same boundary. I have tried in the past to symbolise these shared boundary lines be making one a minus width and one a positive but it never quite works. Also tried making one wider underneath but it doesn't bode well for the legend. Is there a way to make the segment of the adjoining/shared polygons half the width so both colours can be displayed?
Thanks
Mark

[WadeLobb]

Hello

The way I have done this in the past is to convert the polygons to lines and then set an offset for the line under Symbol Selector, Edit Symbol, Cartographic Line Symbol, Line Properties Tab. You can either set one line by the full offset or each by half an offset.

In the past I have only had a few boarders to do so it was easy, if you have lots you may be able to use FEATURE TO LINE for both polygons then do an INTERSECT on the two line FC -  but I have never tried this

[JohnSobetzer]

You can use Wade's approach on polygon outlines as well, but the default symbol outline is a simple line, and you will want to use cartographic lines to have the offset option.

Here's a link to three other options that can produce nice effects: http://mappingcenter.esri.com/index.cfm?fa=ask.answers&q=1116

You can probably find more suggestions like the latter simply by googling on something like the following: ArcGIS tint bands for boundaries

[ScottMoyer]

Mark,
Try all outlines to have the same negative number. For lines with a 3 width I put the Offset at -1.1; -1.5 leaves a visible gap.
Scott