A brief History and a purpose

The recent history is lacking in meaningful published test results and comparisons of HO model train engine performance. What is available seems to be subjective and hard to translate into a easily understandable input for the modelers of 2014. In addition, one sees frequent requests for a comparison of this loco to that loco. For lack of a standardized set of tests, the discussion quickly focuses on the various cosmetic features, paint color, handrails size, dimensional comparison with the full size loco that is being modeled etc. A second topic that comes to the surface almost immediately is a discussion about the Digital Command Control (DCC) features that are inherent to the comparison. While these discussions have their place, they are only a part of the characteristics that impact the overall value of a particular model.

Historically, testing has been done and documented in several forms. (Thanks to Ken K and John from Model Railroad Hobbyist forum for pointing these out.) The last published series of HO scale tests appear to be from the early 1980 time period. (See- http://www.trainlife.com/magazines/pages/509/37017/november-december-1983-page-15)
The mind set of modelers appears to have been different that I suspect it is today. In HO scale, the mainstream model prices were in the $20 – $30 class brand new right out of the box. (Just for reference, that would be around $70 today with 3% inflation per year.) In those tests, the authors were interested in how much better it could be as well as the performance right out of the box. So their tests had several steps, first right out of the box, and then with certain tune ups and additions. The tune ups included the removal of the factory applied lubricants, removing the burs from the gears, lubricating with a high grade set of products and running a break in cycle. The additions were mostly weight, until the motor would start to overheat. Improvements like five wire connections were recommended. But not included in this series of tests. They reported the fastest and slowest speeds of the loco with full wave and pulse wave 12V DC supplies. They also reported the maximum grade loco only. The data appears to have appeared in a print magazine and were highly edited. In at least two cases the values seem either unlikely or inconsistent.
Additionally, other testers were looking to identify loco capacity for pulling the most cars up the highest grade. These were initially published in 1998. The author added data as late as 2011. (See- http://www.girr.org/girr/tips/tips4/tractive_effort_tests.html)
These tests were done for a large scale (G, I believe) outside on existing layout segments. These segments were chosen for grade and curve severity. In this case the author reported current and number of car results. The tests were done by adding cars until the loco wheels started to slip. That defined the no slip maximum number and the current at went with it. Then they added cars until the loco stopped moving and that defined the maximum slipping wheel numbers. In this series, a number of locos were run. Some the same model from the same manufacturer, just different vintage. There are some interesting results. The testing showed how adding DCC actually improved the results. The author also discussed the benefit of scuffed wheels on the results.
I’m sure there are other results from the past out there, but I have not readily found them.
In the past, when a product was reviewed by the model railroad press, a few performance characteristics were included. Maximum draw bar force was reported. This was translated into a certain number of cars on a straight and level track.
In the cases shown in these two reports and the usual data that has been reported, I see limited value to the modern modeler. As in all mechanical systems, because a system does a specific thing well, it does not mean it will do everything well.
Defining a set of test metrics that would cover a range use would be beneficial in many ways. These will be discussed in more detail in other posts.
For now the purpose of this activity is to examine and define a set of performance metrics that can be used to make comparisons between locos and also identify benefits of various features, such as higher conductive wheel material.
In order to define the appropriate test set up and series of experiments to be performed, several aspects of the system, in this case an HO model locomotive, need to be solidified. These include, but are not limited to the following:
The Basic Physics behind the system
What can be measured
What parameters are meaningful to the
The Expected Results The required Test set up
Meaningful test options
And finally, The basic test plan and equipment
Each of these will be discussed in the following posts in this category.

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