For Powell cars headed toward Market Street, this happens immediately, before they descend the steep hill to Pine Street. This is designed to prevent the possibility of cable cars hitting each other at the intersection.)Īfter the Powell cable car crosses the California tracks, it reaches one of the dips in the pavement, allowing it to “take rope” (reattach to the cable). (A little tower on the southeast corner of California and Powell holds a Muni employee who signals with lights to cable cars on both lines whose turn it is to crest the hill. Then, with one hand clanging the bell to keep crossing automobiles from getting in his way, he throws the grip lever forward with his other hand just in time, then coasts with a clatter across the California tracks. The gripman has to crest the hill firmly gripping the cable. Watch a Powell gripman approaching this corner, particularly headed north from Market Street. This can damage both the cable and the grip.įortunately, because of the skill of the gripmen this almost never happens. To prevent the possibility of this happening, there is an alarm system and mechanism under Powell Street on either side of the California tracks to physically force the Powell cable from the grip if it is held too long. If there were no safeguards built into the system, a Powell cable car that held onto the cable too long at this point could pull the lower Powell cable up against the higher California cable and the Powell car’s grip could hit and potentially sever the California Street cable. The Powell Street cable cars, by contrast, must drop the cable from the grip before they cross the California Street tracks. The world’s only cable car crossing, at California (along bottom of photo) and Powell Streets, showing the Cable Car Control Tower on the corner, a fixture at the intersection since 1907.
This means California Street cable cars hold onto the “rope” (cable) as they cross Powell Street. Adhering to the original cable tradition, the California line, which was built first (in 1878) is entitled to the upper cable.
This lowers the car, and its grip, to the level of the cable underneath, allowing the grip to grasp the cable.Īmong other locations, this happens in both directions where the Powell and California cable lines cross. At other terminals (and at other locations on the system), you will see a noticeable dip in the tracks. This lifts the cable upward so the grip can grasp it. Taking and Dropping the ‘Rope’Īt some terminals, you will notice the conductor pulling on a lever in the street. If a cable car is going faster than that, it’s a sure thing that the car is going downhill and the grip is not holding the rope tightly. The cables move at a constant 9.5 miles per hour. The gripman (or gripwoman-two women in history have served in that position we’ll use ‘gripman’ to represent all, uh, grippers) can ‘take’ or ‘drop’ the ‘rope’ (as the cable is called) as needed to start or stop the car. The cables are over an inch in diameter, with six steel strands of 19 wires each wrapped around a core of sisal rope.Įach cable car has a mechanical grip (two on the double-end California cars) which latches onto the cable, much like a huge pair of pliers. As the cable naturally stretches out with use, the wheel is gradually moved back by shop workers to keep constant tension on the cable. When a cable is new, this rearmost wheel is close to the other winding wheels. The rearmost winding wheel in each set is adjustable. Here’s a map.Įach cable has its own set of winding wheels. There are actually four cables, one for the California line, one for Powell Street, and one each for the outer ends of the two Powell lines (Mason and Hyde). All of this was replaced with new but identical-appearing equipment by 1984. Cable car Powerhouse, 1981, showing the giant cable winding wheels and electric motors. There, powerful electric motors (originally a stationary steam-powered engine) drive giant winding wheels that pull cables through a trench beneath the street, centered under the cable car tracks (that’s what’s in that slot between the tracks). The power source is centralized in the cable car barn and powerhouse at Washington and Mason Streets (also home to the Cable Car Museum). Cable Cars have no engine or motor on the cars themselves.
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