Balanced Air Brakes from Scratch

by Daris A Nevil

Fall 2015

During the summer of 2015 I began studying air brakes and how live steam modelers incorporate working air brake systems on their trains. I was well into building a Kitsap Live Steamers caboose kit and decided to add a fully operational balanced air brake system to the caboose.

This is my first attempt at building operating air brakes, and I am quite pleased with the results. Air brakes will certainly be added to my other equipment.

Summary: This article describes how to build Pull-to-apply balanced air brakes.

Equipment



 * Clippard parts:
 * UDR-17-1 : Stainless steel double-acting cylinder, 1 inch stroke, 1-1/16 inch bore, 5/16 inch shaft
 * CT4 : #10-32 to 1/8” ID Hose Connector, designed for Clippard's Polyurethane hose
 * T44-4 : Tee fitting, 1/8 inch ID
 * URH1-0804-BKS : Urethane tube 1/8 inch ID
 * TV-3SP : 3-Way Toggle Valve, ENP Steel Toggle, 1/8" NPT
 * MCV-2 : Check Valve, #10-32 Ports
 * 15090-1 : 1/8” NPT to #10-32 “L” Fitting

Tools and Supplies
The following tools were used in the construction of the truck brakes:


 * Drill Press
 * Low-cost wire welder (110 Volt AC) from Harbor Freight
 * Lincoln Innershield NR-211-MP flux core welding wire, 0.035 inch
 * Lathe (for turning brake shoes and brake shafts)

Plastic Shoes
In 2019 I replaced the aluminum shoes with more realistic shoes printed in black PLA. See Plastic Brake Shoes.

Video Demo
This video demonstrates the failsafe operation of the balanced brakes, along with how to disable the brakes once activated. Video by Daris A Nevil, August 2015.

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