Veritas - Zero-Clearance Tablesaw InsertVeritas’s zero-clearance insert, which features a melamine surface, is designed to reduce tearout on the underside of a workpiece.
A zero-clearance insert offers several advantages over the inserts with wide clearances included on most tablesaws. The kerf in a zero-clearance insert is no wider than the blade, which helps reduce splintering. When ripping, a zero-clearance insert prevents thin offcuts from becoming trapped between the blade and the insert, an event that can send the offcut rocketing back at the operator. A zero-clearance insert also cuts down on the amount of sawdust that gets blown out of the throat of the saw. And it helps reduce noise.
You’ll find zero-clearance inserts at most woodworking-supply outfits, or you can make your own, but I especially like the ones marketed by Veritas. They’re made from 1/2-in.-thick high-density phenolic laminate, a material that’s stiff and durable. To help workpieces slide easier, the inserts are coated with melamine.
Adjustment screws on one end and side of the insert ensure a perfect fit in the throat. And four leveling screws, accessible from the top, allow you to adjust the insert so that it’s dead flat. An end pin helps keep the back edge of the plate from lifting during a cut.
On many saws the blade won’t lower more than about 3/8 in. below the tabletop. So a new 1/2-in.-thick insert can’t be fully inserted in the throat. And with the blade touching the underside of the insert, there is no safe or easy way to make the kerf cut. But a shallow groove on the bottom of the Veritas insert provides clearance for the blade, so you can start the blade before slowly raising it up into the insert.
I encountered only one problem along the way. When the insert was first added to my tablesaw, the end pin butted against the radius on the underside of the throat. The interference was less than 1/16 in. but just enough to keep the insert from sitting perfectly flat. A Dremel tool with a grinder provided the needed clearance.