Upcut Spiral Bits pull chips (and your material) up and away from the table (with upcut, the airplane propeller spins the correct direction). They are great at clearing out chips from your cuts to avoid overheating your bits and therefore excel at making deeper cuts. Because of the upcut direction of the flutes, the tradeoff is that these bits have a tendency to splinter the top surface of sheet goods like plywood and melamine coated particle board. You also need to be very sure that your material is securely held down to the table so the bit doesn't lift it while cutting. - - - Maker Made CNCs solid carbide router bits are designed to handle a variety of materials with ease. The up cut bit is designed to move chips away from the cutting surface leaving a perfect bottom surface. The upcut router bit is perfect for the Maslow CNC and other CNC machines.