After checking out Sandra Straits Chambray tangle description on SB's most current blog post, I decided to give it a try. Used a pilot blue gel pen - how appropriate, huh? I used the shading technique she described but decided it needed some additional line work to enhance the fold forms against the blue. Not sure it's working, or where this fuzzy little fold guy is going, but it's was a change of pace using a color pen.
Using black ink does make the lines "pop" and I found using the color pen a little more challenging. The black and white makes it easier to focus on the lines and forms, adding color creates its own issues. Not sure if I like the final product but the textures are fun.
I want to try sepia pens some time. I've seen tangles on the flickr zentangle group done in sepia that have an interesting aged feel.