Well done! I love the spacing, very eye appealing! Love it!
I have done mostly brass in the past, but they are hard to make. I took a sheet of brass .5mm and placed between two pieces of 1/2 inch plywood, screwed the edges of the ply together and then drilled holes on a grid. After that, I unscrewed the plywood, took the brass sheet out and cut the brass. It warped the brass for sure, but I would then put the cut out pieces on an anvil and tap them with a hammer to flatten. Worked well. I haven't done segments in a while and your pen is certainly is nice, makes me want to make one, or two or three!