Cable Stop

A cable stop is a small cylindrical or barrel-shaped metal fitting attached to the very end of a garage door lifting cable. To install a cable stop, a technician threads the cable end through the slot in the cable drum, then the cable stop is swaged (mechanically compressed with a crimping tool) onto the cable end so its diameter is larger than the slot opening. When the door closes and the cable pays out from the drum, the cable stop seats against the outer face of the drum and prevents the cable from pulling through.

Swaging is the key manufacturing process. The fitting starts as a straight-bore sleeve that slips over the cable end. A swaging tool compresses the sleeve radially, deforming both the sleeve and the outer strands of the cable together. The result is a permanent mechanical bond that holds to a rated pull-out load without relying on knots, which would weaken the wire strands, or threads, which would loosen under vibration.

Why cable stops matter:

Without the cable stop, the only thing keeping the cable in the drum slot during a full open cycle is the tension of the spring system. If the door is left fully open for an extended period and the spring loses a small amount of set, the cable could go slack and work its way out of the slot. On the next closing cycle, the cable would not wind onto the drum correctly and could wrap around the shaft or jam in the track.

Cable stops are a wear item. The cable wire can fatigue just at the entry of the swaged sleeve, where the bending radius is small and the motion reverses on every cycle. A cable that breaks at the cable stop end - rather than in the middle of its run - often shows fraying or broken strands at the sleeve edge before the full failure.

When a cable is replaced, a new cable stop must be installed. Reusing an existing stop by sliding it to a new position is not acceptable because the swage deforms the sleeve permanently to the specific cable position it gripped.