In March I joined the Vancouver Urban Sketchers at the Pacific Central Station in Vancouver. It is a huge long building with great architectural elements that was fun to sketch.
My challenge was that within the time allotted (3 hours), I only completed the pencil drawing of the structure, and applied only the sky color in the sketch. This was done in a 11.5" x 8" Moleskine Art Journal. The paper weight is only 90LB, and it cockled and warped even though I had alligator clips on three sides to secure the paper.
It started to rain, and we had to pack up all of our stuff and head inside to the station, where we showed our work to each other and chatted about the days efforts.
After I got home, the drawing was inked with my Lamy Safari pen, and I finished the remainder of the watercolor.
In terms of the future there are two elements that need to be worked on.......First will have to go earlier to each meetup, perhaps a couple of hours earlier, and Second to use 140LB paper from now on so that the paper does not cockle and warp when watercolor is applied.
All & all it was great fun with the group, and for those of you who want to give Urban Sketching a try, you will find that the goal is not to create a masterpiece, but just to enjoy the sketching experience with a group of great creative people.
Brush pens, and did a quick portrait study of one the folks in our group, talked at great length at how to use the pens with different values and how to apply them to various types of paper, including toned paper. 
