I have several sheets of old newspaper printing press tin. They were outdoors and are extremely dirty but the print is still readable - I would love to clean the grime but every product I try wants to remove both grime & ink - any suggestions?

  

Hi Julie. I have no printing experience, but from a few minutes on the web, these sound like aluminum lithographic plates.

Although the situation sounds pretty hopeless, the principal of lithography was that the oil-based ink would not mix with water, even a great deal of water. So maybe just long soaking in water will remove a fair portion of the grease without removing too much of the ink. Lacking that, I'd try gasoline as the grease remover because it works very easily on most petroleum based greases but may have less effect on the ink. Obviously gasoline is very hazardous from many aspects including flammability and poisonous fumes, so it must be used outside, and in very tiny amounts. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey