N Scale Steam - limitations?

Piculous???

I thought profanity was not allowed on this forum. [swg]

Rich

This is based on my experience with small HO and HOn3 steam.

The typical shortcuts taken for model locomotives become bigger performance issues in N size steam. Things like rigid frames, lateral motion of drivers for sharper minimum radius, single piece side rods, lack of extra ele

Fred,

Lot’s of good thoughts but unfortunately, most of them don’t transfer well to N scale. Belts just wouldn’t work in N, they are too stiff and would cause a lot of start up drag. As far as side rods go, ridgid side rods seem to help N, not hurt. They help keep all the drivers in time. If you have ever played with a ConCor Big Boy, you would understand why individual side rods just don’t work that well. Between the slop in the gears and the slop in the side rods, there is too much slack action in the drivetrain that causes binding and kinks in the operation.

As far as the metal boilers go, Bachmann has that licked. The last 4 releases from them have had metal boilers. They have their casting process down to the point that their metal boilers are as sharp and detailed as plastic. The most recent announcement from them the 2-10-2 Light is another with a metal boiler.

I have one brass loco, a C&O H-8 (2-6-6-6). As much as I love the loco, I will put any number of plastic loco’s up against it in both pulling power and smoothness of operation. Brass is generally not a better runner than plastic anymore.

[swg]

From my experience with 19th Century HOn3 - which is often smaller than large steam N - the means to better performance are known - but are not often used in mass production due to expense and/or difficulty in reproducing on a mass basis.

Of course, one needs to define good performance. My threshold of acceptability is:

  • smooth running at 3 scale MPH or less on normal DC (with 120 Hz ripple). Smooth means being able to push a cut of cars equipped with free-rolling trucks in delayed uncoupling mode without cars separating or lurching. Meeting this requirement is key to enjoyable switching operations.
  • maximum speed at 12 volts no more than 20% greater than the prototype’s capability. This requirement gives a decent c