Boston PCC Solid Wheel History

Boston PCC Solid Steel Wheel History

All Boston PCC cars were air-braked except for 25 All electrics bought as a favor to Pullman Standard ‚ P-S needed experience in building the 1945 all-electric model ‚ so the MTA obliged. The operators never liked them, however ‚ as the cars were free-wheeling ‚ when the GE brake was released ‚ allowing the car to drift backwards or forwards on a slope. The air cars had a delayed brake release. The air cars also had either tread brakes or air operated drum brakes on the motor shafts. Through the years ‚ the MTA converted many tread brake cars to drum brakes. Toward the end of PCC operation on the surface-subway lines ‚ the decision was made to go back to tread brakes. Even the picture-window cars got them ‚ despite the fact that they were built with drum brakes.

Resilient or Solid Wheels

The solid wheels were introduced long before any changes were made in brakes: around 1960 ‚ the super resilient wheels on the Riverside line picture windows cars were gradually changed out to solid wheels. (Don't forget that CTA in Chicago was doing the same thing on their PCC rapid transit cars). The MTA allegedly said that the resilient wheels were becoming loose due to high speed running on the Riverside line. Whatever the cause (expense of resilient wheels comes to mind) the MTA gradually changed out all of the resilient wheels for solid steel so by 1964-66 all PCC cars had them. As you know ‚ all of the CTA PCC rapid transit cars got solid wheels during the same time ‚ Universal air-wheel tread brakes came back with the PCC rebuilding project in the early 1980s. Eventually the remaining air cars, including picture window cars, got tread brakes. The Arborway line had the last air-electric cars with tread brakes using the central subway. After December 1985 ‚ only the Mattapan-Ashmont line still used PCC cars.

The all-electric cars were in a minority and in 1960 were converted to MU using GE multiple unit controls. The braking issues were resolved by then. Two-car trains of all-electrics ruled the Arborway line until 1977 when all of them were retired and junked.

The present day Mattapan cars (8) have solid wheels with sound dampening pads fixed to the hubs. The deafening squeals produced by the cars taking the Ashmont loop caused howls of protest when the new station was opened for service, prompting a search for a solution. The MBTA said that resilient wheels were unobtainable (!) even though every other PCC operation the country had no problem getting them. Tony Tieuli