In reply to paul_in_cumbria:
> The Griptonite app gives the problems Font grades.
I used to like that but I can no longer see it - the app seems to just have the ER grade bands (except for the circuit board) as far as I can see. Am I missing something?
> I think there’s a board somewhere which has conversions on it.
Yes, there's a board which tells you what grade bands the different numbers cover. I assume they are font grades. So IIRC 3 is F6a and F6a+.
Post edited at 09:45