Stains on BL18 foot

This may be the most obvious fist step and I think you have probably tried it already: Cleaning with rubbing alcohol. You could also try different cleaning products. It would really be a surprise if you could not remove the stains by cleaning. If they do persist however, I would probably just use some black marker and paint over the spots, not the perfect solution, but the cheapest.

Beosince98:

This may be the most obvious fist step and I think you have probably tried it already: Cleaning with rubbing alcohol. You could also try different cleaning products. It would really be a surprise if you could not remove the stains by cleaning. If they do persist however, I would probably just use some black marker and paint over the spots, not the perfect solution, but the cheapest.

My wife tried first with alcohol, no success. I will try other solutions and report back. If it does not work I will spray some black paint on it.

However, I have to admit that I am more curious about how they got there...

The Pink Stuff cleaning product is worth a try as that stuff is brilliant. There's nothing it hasn't cleaned perfectly for me in lots of uses.

Ravsted:

Water with a small amount of soap.

Gently brush with old soft toothbrush.

Looks like moisture. I believe they are made of cast iron and moisture will more likely condensate on that (cold) surface.

Has the edge of the aluminium touching the cast iron feed also started to corrode? Looks a bit like that on the first picture.

 

No it’s not corrosion. It’s actually a thin bit of plastic that comes out from the hole for half its diameter.. No idea what it is, it’s the same on all the other speakers. I will unscrew them tomorrow and check. So strange to have moisture here though. I will swap the speakers to see if it’s this particular corner of the room. 

Ravsted:

Water with a small amount of soap.

Gently brush with old soft toothbrush.

Looks like moisture. I believe they are made of cast iron and moisture will more likely condensate on that (cold) surface.

Has the edge of the aluminium touching the cast iron feed also started to corrode? Looks a bit like that on the first picture.

 

No it’s not corrosion. It’s actually a thin bit of plastic that comes out from the hole for half its diameter.. No idea what it is, it’s the same on all the other speakers. I will unscrew them tomorrow and check. So strange to have moisture here though. I will swap the speakers to see if it’s this particular corner of the room. 

Did you have a plant in its vicinity? Sometimes they leak drops through their leaves..

Ravsted:

Water with a small amount of soap.

Gently brush with old soft toothbrush.

Looks like moisture. I believe they are made of cast iron and moisture will more likely condensate on that (cold) surface.

Has the edge of the aluminium touching the cast iron feed also started to corrode? Looks a bit like that on the first picture.

 

Thanks for the tip, the most obvious and easiest solution are the best. Some Dove liquid soap took care of it!