Aside from the materials they are made of, bits can be classified as edge bits or non-edge bits, and whether the bit is designed to be anti-kickback. Edge bits have a small wheel bearing to act as a fence against the work in making edge moldings. These bearings can be changed by using commercially available bearing kits. Changing the bearing, in effect, changes the diameter of the cutting edge. This is especially important with rabbeting/rebating bits. Non-edge bits require the use of a fence, either on a router table or attached to the work or router. Anti-kickback bits employ added non-cutting bit material around the circumference of the bit's shoulders which serves to limit feed-rate. This reduces the chance that the workpiece is pushed too deeply into the bit (which would result in significant kickback from the cutting edge being unable to compensate).
Aside from the materials they are made of bits can be classified as edge bits or non-edge bits and whether the bit is designed to be anti-kickback Edge bits have a small wheel bearing to act as a fence against the work in making edge moldings These bearings can be changed by using commercially available bearing kits Changing the bearing in effect changes the diameter of the cutting edge This is especially important with rabbeting/rebating bits Non-edge bits require the use of a fence either on a router table or attached to the work or router Anti-kickback bits employ added non-cutting bit material around the circumference of the bit's shoulders which serves to limit feed-rate This reduces the chance that the workpiece is pushed too deeply into the bit (which would result in significant kickback from the cutting edge being unable to compensate)