1.5 mm

boilerplate:  Primers are kind of fun things to put together, at least in my opinion.  You end up calligraphing every letter in a given alphabet, multiple times, and end up having to stretch brain muscles to make things fit whatever theme you’re going with.

So have a tumblr/’net primer.  Complete set will end up under this tag here.  And if you think there’s something that might have worked better for a particular letter, let me know.