End of last year for whatever reason I got several mails/calls from people who had to deliver their subtitles formated with a fixed amount of characters per line.
If you do burned-in subtitles within FCP or bitmap subtitles it's quite easy with the right text generator or app -- if you need to export for another format it's a lot of work.
I told those people to do a video tutorial, but while trying to do I saw that I can do the work fast and those others couldn't follow.
So I did a little app which does process a Spruce text STL and breaks the lines at a given amount of characters.
There is no web page for the app now, but you can download the
help PDF here -- from the PDF you can download the app for free.
Andreas