It would be a long time to sand down your heads to the point that you speak 
of.....I just shudder at the thought of the abrasive cleaners - but I imagine 
it would take years of using the "tape" variety cleaners.  There is a happy 
medium though, if you get one of the cleaners that is a "wet" type, that is 
that you place the cleaning solution on the cleaner first, it's not as bad.  
In my humble opinion though, the BEST method is the open themup method, as 
you can inspect all your pieces/parts and look for trouble before it starts ! 
  Happy Video-ing !!!!
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