My hybrid tablesaw has a 1⁄8"-thick metal throat plate that sits in an opening with very shallow ledges. This shallow recess complicates making a zero-clearance insert (ZCI) for the opening in order to minimize exit tear-out and prevent narrow rippings from falling into the saw. My solution is to modify the stock throat plate.
Make a sub-plate by cutting a piece of 3⁄8"-thick plywood to fit between the leveling screw tabs in your table opening. Wax the underside of the stock plate and the inside edges of its slot (to resist glue when attaching the filler strip later), and then screw the plate to the plywood with flathead screws driven through six countersunk holes you drilled through the plate. Next, thickness a hardwood blank to match the width of the slot, and then rip from the blank a strip that’s just a hair wider than the thickness of the plate. Crosscut this slot-filler strip to the slot length, and then glue and clamp it to the underlying plywood, topping the strip with waxed paper and a caul. After the glue dries, sand the strip flush to the plate. (To avoid scratching your plate, mask off the surrounding area with tape.) Alternatively, unscrew the stock plate, and hand-plane the strip, testing the fit as you work. Finally, clamp down the finished ZCI, and raise the spinning blade through it.
—David Schermock, Humble, Texas