Hello everyone. I recently sold a Realforce 91-UDKG to a member. As I was taking the keys off to clean it to get it ready to ship out to him I noticed that tiny rust spots here and there developed across the black metal plate the switches are all stuck to; the plate which is on top of the circuit board directly under the key caps. I was unaware this rust was there because with all of the keys on I can' really see it unless I'm tilting it in the air above my head looking under the keycaps. I always babied my board and even covered it when I wasn't using it so this was a shock to me.
I bought this keyboard in Japan around a year ago and the entire time I used the keyboard I was living in Japan. It's a pretty humid country. I'm guessing this is why just the top of the board has the rust, where it was exposed to air more.
1) Is this a normal development on the metal plates of keyboards? 2) Is this harmful to the board or only cosmetic? 3) Is this something that can be cleaned or covered up?
I told the buyer of my discovery and told him I'd research this to make sure it's nothing abnormal before shipping it out tomorrow so your help would be appreciated.