Bits&Bits SF525 Surfacing Router Bit Kit (Includes inserts & wrench)

For slab flattening by hand, router RPM should at 12,000-14,000RPM, depth of cut at least 1/16-1/8″ depending on wood species, and overlap your passes at about 50% (in other words, take about a 1-1/4″ wide pass at a time).

For flattening on a CNC machine, set the spindle speed at 12,000RPM, 150-250IPM (depending on your CNC),depth of cut at least 1/16-1/8″ depending on wood species and overlap your passes by 50%.

Things to watch for; make sure you’re cutting chips and not dust. If dust, slow down the router or take a deeper cut. If burning occurs, slow down router or take a deeper cut. Also, depending on wood species, you might need to clean the bit often to make sure oil and dust don’t build up and cause burning. Soaking in a bit cleaner, solvent, simple green or even liquid laundry detergent for up to 30 mins then brush off with nylon or brass brush.