On Mar 25, 2:16*pm, Han wrote:
Larry Blanchard wrote in news:imihno$sg3$1
@speranza.aioe.org:

"Shellac will continue to dry and harden for several years, depending on
the environment, but a couple weeks is usually sufficient for normal
handling and polishing."

And I know he meant that to be shellac in general because he has said so.

(Not an expert by any means, but my 2¢, free of charge):
In my experience, thin layers of shellac dry to "hard" almost within 10
minutes. *After some more time, it may eventually become "rock-hard".

Dry to the touch in one second if you're French polishing,
two hour wait between sessions is enough to prevent
ridging.