Adding anchor points offset from intersections automatically in Illustrator

Question

I'm a stained glass artist using Illustrator to create patterns and cutting templates. I'm always looking for ways to simplify and automate things.

My designs are ultimately just a series of paths crossing each other on a simple Illustrator artboard. Here's a zoomed in example of an intersection of two paths where 4 pieces of glass would meet.

I'd like to automatically have the paths be a different stroke width or color a specific distance (say for example, 2mm) leading up to the intersection along each path, to speed up measuring the lengths of joining material that happens at these intersections. I know that I can do this manually by creating a 2mm circle centered at the intersection, using Pathfinder->Outline, and deleting the parts I don't need. This then lets me control and stroke or color the lines leading up to the intersection, as needed.

For small designs, this workflow is fine. For large designs (100s of intersections), this would be pretty tedious, and not worth the effort. Is there any way to automate this a bit using the path offsetting tools or scripts or something?

Answer 1

An option (without scripting) is to add another stroke to your paths in the Appearance Panel (Window> Appearance). Put this stroke under the original stroke and make it wider than the original stroke to suit the particular offset proportions you need. I made the added stroke white and set just that strokes blend mode to difference so that it is only visible where the strokes overlap.

In the appearance Panels top right drop down menu uncheck "New Art Has Basic Appearance" so that all your new lines will have this appearance.

You can also save this as a Graphic Style (Window> Graphic Styles) for future use.

NOTE- This will not give you added anchor points but merely a visual cutting reference. If what you need is actual anchor points at these intersections it would require expanding and shapebuilder or pathfinder.