What is a Ball Bearing Guide?

A ball bearing guide is a reference to a part used in conjunction with the cutting tip of a router to ensure smooth precise cuts. The ball bearing guide is a closed wheel-like casing that is attached to a shank or bit-spindle on a router. The ball bearing guide rolls along like a wheel and is placed in contact with a jig or edge surface to help steady the movement of the router while cutting. This type of guide is critical for ensuring smooth and steady cut moldings and finishing.

A ball bearing guide does not come in a standard size. The size will be dependent on the size of the cutting bit and the bearing’s relative location. Some bits have a small bearing located below the cutting tip to help in cutting moldings or edges because this location will also act a horizontal “depth” gauge. When the ball bearing is located above the cutting edge of the bit, then it will serve as a guide for deeper multiple-pass cuts, but it can only be used once that depth has been reached. If the ball bearing guide does not rotate freely, then replace it immediately with the same size as this will guarantee its continued effectiveness.