Yes, I use various drawing aids to do the box lining and other details:


The pieces of 3/4 x 3/4 x 1/16 aluminum angle are for drawing the longitudinal lines, and the thick zip tie is for drawing the rings around the tubes. I find the main problem with the pens is that the results look too perfect. Original box lining was done freehand with a pinstriping brush, and the slight imperfections are part of the look. I tried a pinstriping brush, but just couldn't get good enough in the time I was willing to devote to practicing.