The idea is to make a class (?) for the dot matrix font that makes a circle depending on an array of parameters that are 1 and 0. And then create a library of characters that actually are arrays of 1's and 0's.
The advantadge over a font is that with dot matrix everybody can create custom characters (japanese hiragana, russian, arrows, etc…) just by changing the 1's and 0's. Also the dots could be as small as the milling bit.
I am now researching what would be the best matrix size (nxm dots) in order to be as universal as possible.So far I found that 5x7 was a standard back in the old dot matrix printers allowing numerals, uppercase and katakana. So that would be my starting point.