I have restored several Iron cases before. Also, I have found that the best method to remove the original enamel finish; if the original is too far gone. Completely disassemble the case. I've had access to a beads blaster (pecan or walnut shells) in an aircraft hangar. The beads blaster works amazingly. You never want to use a traditional sand blast method. Then I used steel wool to the bare iron. Place in an oven at 300 degrees, to remove any moisture in the iron for about half an hour. Steel wool one more time for possible surface rust. Be ready to pack all the iron in cloth. I took my clock case parts to a friends auto body shop. They sprayed the parts, while hanging on trimmed coat hangar wire with their auto primer. After the primer cured, the parts were sprayed with (my selection) Honda Accord Black Enamel Paint. Then, when I took the parts home I let the paint cure, for about three weeks. Still disassembled, I used Meguiar's Deep Crystal Carnubu Auto polish, of several coats. Carefully reassemble the case, and buff for fingerprint smudge with a soft clean tee shirt. The case looks like it had to of been when new. Right from the assembly factory. Never any complaints, all compliments. I tell people that if you saw the clock before, you wouldn't give it a second look. I will be doing this again on a cream white Ansonia iron case soon.