There is a device called a NiC sander available from,Pro Motorcar Products, used by the body shop guys.,available at most automotive paint stores. It is like a pen shaped instrument with an insert of fiberglass that can be adjusted out when it wears down,the bristles of fiberglass make short work of small sanding areas. without a lot of uneccesary damage. here is the website www.promotorcarproducts.com