[Drake] B-Line chassis cleaning

[John Barnwell via Drake]

I am finally getting around to setting up my B twins and am seeking some advice.

I have never cleaned the chassis on these pieces and there is only a very fine layer of dust/dirt sitting on pristine, corrosion free copper cladded chassis. With the C twins I simply used a mild solution of simple green on followed by quickly drying. I'm concerned that by doing this with the B twins on that copper, that I could start a corrosion process in doing so. Would someone please steer me towards the right product to accomplish this simple task, without doing harm to this beautiful copper? Also, did Drake use any type of conformal coating on this copper chassis, or is it simply naked copper cladding?

On another subject, the VFO knob skirts ride against a spring washer to maintain pressure. It would appear that this washer actually eats a groove into the backside of the skirt. I can imagine that decades of use might actually wear a very deep groove into the skirt. Again, on the C-Line they seem to have addressed this issue. Any elegant solutions to prevent this wear?

These pieces came from an original owner who apparently never used them other than sitting out for a while collecting that dust I speak of. They still have that "new electronics" smell.

Thanks for reading and any forthcoming advice,

John Barnwell KE7TPA