I have an antique typewriter in perfect condition was my grandmothers yesterday

while cleaning? I did an experiment and tried windex to shine it up and the rag turned brown, so I thought there was something on it and so I squirted the windex on to the typewriter and wiped it now when you look at it in the light you can see the squirt marks and they won't come off, what can I do to fix it? It is made out of a black steel.
 
Back
Top