1
general::
Produce, especially on a keyboard, as in I can pound out another résumé, or She was pounding out song after song on the piano. [c. 1900]
American Heritage Idioms
2
general::
Phrase(s): pound something out
1. Lit. to flatten something by pounding. • He pounded the gold leaf out very thin. • He pounded out the gold leaf. 2. Fig. to play something loudly on the piano, perhaps with difficulty or clumsily. • Here, pound this one out. A little softer, please. • She was pounding out a nice little tune. 3. Fig. to type something on a keyboard. • I have finished writing it. Can I borrow your laptop so I can pound it out? • All the reporters were pounding out stories for the next edition of the paper.
McGrawhill's American Idioms And Phrasal Verbs