I have acquired an 1851 Navy Colt revolver with brass frame. The cylinder is seized solidly to the pin presently. I have completely disassembled the firearm and have tried using penetrating oil on the cylinder and the pin in hopes to get it to break free so I can clean the both separately. However that is not proving to do much of anything other than get me all oily. I have also tried using soft tools to tap the cylinder loose to no avail. Would heating the frame, cylinder and pin prove useful or should it be avoided due to the brass? I have seen it recommended for steel frames, never brass. Short of replacing the frame, pin and cylinder, I am running out of ideas.