Ask MR.

The article "Ask MR." from Model Railroader provides answers to various questions related to model railroading. The first question addresses the purpose of the bars on top of Pennsylvania RR diesel locomotives, which were actually train-phone antennas used for communication. The article explains how the train-phone system worked through electrical induction and its limitations on electrified routes. The second question discusses the uses of isopropyl alcohol in model railroading, such as cleaning wheels, track, and parts, as well as its role as a wetting agent and thinner for paint. The third question explores the location of the water filler on old wood-burning steam locomotives, explaining that it is typically hidden by firewood on the back of the tender's deck. The fourth question addresses the use of timetables for short line railroads, emphasizing that timetables are important tools for any railroad with multiple trains to prevent traffic jams and collisions. The article also mentions different methods of traffic control systems in model railroading. [Extracted from the article]