Horological Meandering

Hello everyone, I need your help and advise in case you have already faced the same problem. I have a vintage skeleton which is not working properly. I have used a loupe / magnifying glace and found very strange brown (sticky?) spots on some of the wheels...  

Hi, That's obviously rusted steel parts, as can be seen other non steel parts seem unafected. Your watch is in urgent need of some good restoration, obviously humidity entered the case and did a lot oft harm.... Best regards Suitbert

Thanks SuitbertW and Ancienne Le Brassus for your feedback. I have shown the watch to a friend of mine who is watch maker and he believes that it is not rust. You are right, the brown thing is only on the steel parts and not on the gold part. But it seems... 

... but even if it is mould it indicates that there is moisture inside. The most likely explanation is still rust, though. Either way it requires a service to prevent further damage and hopefully salvage the damaged parts. Which AP do you have, Alkiro? Ca... 

Dear all, See attached pictures of the watch. Not sure it can really help you but it was not easy to take them. Note that there is, in addition to the brown substance a red strange thing on the third picture (again, the red thing is inside the watch, on t...  

... as it can behave in unusual ways. Best let a watchmaker diagnose the problem. And please let us know what you decide. Andrew

certainly looks like rust, considering it has only affected the steel parts. This could either be due to humidity entering the case or improper/insufficient cleaning during a service. The old type (ammoniated) cleaning solutions can rust steel parts if no... 

...as I also thought it looked like rust. Could it be brass "dust" from worm gears, perhaps mixed with oil, causing it to look sticky?