Future reference (geddit??):
Now on, anytime you finally get around to something and wonder if the 'cals are baked, guess what - they prolly are.
Heah whut y'do:
Coat that lovely artwork with a clear acryl varnish (such as Future or Kleer or Shazam Floor Wonder), let it cure, cut out the questionable cal and soak extra long in the dish until confident.
Place that Rare Thin on yer build and On Down The Road Wid Ya.
Had some extra thin roundels blow up on an M1.c and almost called 911.
This was the saver.
When in doubt, Create-A-Coating.
Make ya famous.
(There is a highly technical, hysterically-based, world wide, award winning answer to this same concern and it makes for fantastically lucid, spirited reading, but in the meantime, in between time, this will do.)
Such things are termed: Tricks Of The Trade
Amazing.