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In the open type, feedwater was sprayed directly into a mixing chamber containing exhaust steam, condensing the steam and raising the water temperature. Feedwater heaters made by Worthington were of the open type (Figure 1).
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In a closed type, heater water was fed through an array of pipes inside a large chamber filled with exhaust steam. The feedwater and steam did not come into direct contact. Both Elesco (Figure 2) and Coffin (Figure 3) manufactured closed feedwater heaters.
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Figure 1: Worthington feedwater heater on a HO scale KTM model of a SP F-5 class 2-10-2
Feedwater heaters use the heat in exhaust steam improving efficiency.
(click here)
— Richard Bale
QUESTIONS AND ANSWERS Q: I’m going to build my first layout in N-scale. I thought a 4x8 would be good. Is this true? A: An N scale 4 x 8 layout will almost always look more realistic than an HO layout in the same space, but access and reach issues must be considered. To allow a 2-foot (very tight) access areas around three sides of a 4 x 8 foot layout, the railroad actually occupies a minimum footprint of 8 x 10 feet. An around-the-walls layout in that same space will have better access, a more linear (and longer) mainline, plus the center of the room is available for viewing or other uses.
If you absolutely must build a table layout in N scale, consider 3.5 x 7 feet. It still offers many of the “trains running through big scenery” advantages of N scale but doesn’t take up as much room. For a neat N scale layout this size, see “N Scale Railroading, An Introduction to the Hobby - 2nd edition” (Kalmbach Books). — Marty McGuirk Q: What is a steam locomotive feedwater heater? Why were they used? A: On steam locomotives, a device called a feedwater heater used exhaust steam to preheat water from the tender before it was injected into the boiler. There were two basic types of feedwater heaters; open and closed.
Page 32 • Issue 9 • Sep/Oct 2010 • MRH Questions, Answers and Tips, page 1
Q: What differences are there between first and second generation diesels? When did the second generation come along? A: Second generation diesels are generally considered to be those that started replacing first generation diesels instead of steam engines. They were also the first models commonly equipped with turbochargers and producing 2000 hp or more. The second generation began with the introduction of the EMD GP20 and the GE U25B in 1959 and the GP30 in 1961. Source: http://www.american-rails. com/diesel-locomotives.html.
Figure 2: Elesco feedwater heater
(courtesy Central Vermont Railway Historical Society)
Figure 3: Coffin feedwater heater
(courtesy Central Vermont Railway His-
— Jeff Shultz
torical Society)
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