Heisler Park Brake
Nelson Riedel, Nelson@NelsonsLocomotive.com
2/20/2010, last updated 02/20/2010

The front and tender trucks are equipped with air/steam operated brake cylinders.  There was no room for a brake cylinder on the middle truck so it was decided to make the brakes on the middle truck mechanically operated park brakes.  This page describes the park brake mechanism. 

The photo at right shows the park brake handle which is located beside the Johnson bar.  The handle is essentially identical to the Johnson bar except that the paw is sloped so that the handle can be pulled back without lifting the paw.  The paw must be lifted to release the brake.
This is a close-up of the paw and the linear ratchet.   The ratchet was made from 1/4" square bar.  The ratchet teeth  were cut with a saw and then smoothed with a file.
This shows the Johnson Bar and park brake lever from the rear.  The park brake lever is next to the cab side and hopefully won't be too noticeable since it is not prototypical. While the handle is essentially identical to the Johnson Bar (See Johnson Bar), it was made from a drive shaft that had been cut too short.

 

Photo above shows the park brake shaft and arm as viewed from below the locomotive.  

The shaft is 3/8" diameter CFS stock and the arm is made from 3/4" X 3/16" HRS flat stock.  The arm is silvered soldered to the shaft.  

A pair  of the bearing blocks shown on the right support the ends of the shaft.  Flanged sleeve bearings (3/8" ID - 1/2" OD) are fitted in each bearing block.  A pair of shaft collars(McMaster) keep the shaft positioned properly.

The park brake works great!