A work bench includes a table secured on top of a base and having a pair of parallel grooves. Two pairs of sprockets are rotatably secured to the table and extended inward of the grooves. Two endless chains are engaged with the sprockets and each has a portion slidably engaged in the grooves. A guide is secured to the chains and moveable in concert with the chains. Two couplers are secured between the guide and the chains. One of the couplers includes a downward dependent ear for slidably engaging with the table. A quick release device is secured to the other coupler for engaging with the table and for locking the guide to the table. The guide may be quickly adjusted relative to the table when the quick release device is released.