Air brakes

External References

 * Gerry Stuteville's "Auto Air Brakes"
 * "Affordable Air Brakes by Harry Haas"
 * "Real Brakes for Model Railroaders"
 * "Cup Seal Vacuum Motor", Lee Nonnemacher, Pennsylvania Live Steamers
 * "Air brake question", Chaski.org
 * "Freight Car Brake Rigging Arrangements", Wabtec Corp (PDF)
 * "Wabtec Freight Catalog" (PDF)