Not sure what sander you bought but in my opinion you never want to use an orbital sander on fret work. The paper can catch and rip delicate pieces apart. I like to use a 1/4 sheet palm sander and my go to sander for over 35 years has been this Porta Cable Bloc sander. It is a work horse and and is delicate enough for fret work. I believe these are not available for sale any more. Not sure.
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