Uncommonly shaky painter of 2 resting on stack (8)

I believe the answer is:

ricketty

I'm a little stuck... Click here to teach me more about this clue!

'2 resting on stack' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'uncommonly shaky painter' is the wordplay.
'uncommonly shaky' becomes 'rick' (I can't justify this - if you can you should give a lot more credence to this answer).
'painter' becomes 'etty' (I've seen this before).
'rick'+'etty'='RICKETTY'

'of' acts as a link.

Can you help me to learn more?

I've seen this clue in The Telegraph.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.