A rep from 3 M did a presentation to the Silicon Valley Woodturners club. Two Coated Abrassives Manfuacturers Institute (CAMI) booklets from that presentation, "CAMI Book #1 - Coated Abrasives.pdf" and "CAMI Book #2 - Woodworking.pdf" provide more than you probably ever wanted to know about abrassives and their application to woodworking
Look for "3 M handouts" and click on CAMI Book #1 and CAMI Book#2 to download their PDF versions. Note: these are relatively large files so if you have a dial up connection to the Net be prepared for a long download time.
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