Two-in-one insert for extended life
I use a zero-clearance insert for making nearly all tablesaw cuts, so I go through a lot of them. To extend the life of your inserts, simply rotate them. First use one side with your thin-kerf blade. When it gets chewed up enough to start losing effectiveness, designate that slot as the full-kerf side or another thin-kerf, and turn the insert around. The fresh side becomes zero-clearance for the thin-kerf blade once again.
—Craig Richardson, Ottumwa, Iowa