Measuring Drawbar pull on Locomotives

[ttrigg]

IRB Souther Engineer

  http://www.micromark.com/DIGITAL-PULL-METER,9577.html

I found it by accident. I'd like to get one at some point.

Very Interesting.

[IRB Souther Engineer]

 http://www.micromark.com/DIGITAL-PULL-METER,9577.html

I found it by accident. I'd like to get one at some point.

[kstrong]

Well, I could tell you I've got a $250 spectral analysis machine that measures the stresses on the couplers to arrive at drawbar pull. And if you want to believe that, feel free. Alas, I use a simple kitchen scale. It goes up to 3 pounds, which has proven adequate for all but one or two locomotives I've reviewed. For those, I used the even more high-tech solution of seeing how many dead locomotives it could drag. (When you get into measuring drawbar pull by seeing how many dead locomotives you can pull, "average" pulling power is pretty much academic.) 

In terms of how pulling power equates to the number of cars, a very general rule is 1 car for every 1.5 ounces of pull. Throw curves and grades into that mix, and that number decreases dramatically. A locomotive with 20 ounces of pull (a bit of a lightweight) will handle around 4 cars on a 4% grade. (Much also depends on how smooth-rolling the trucks are, the weight of the cars, and a good number of other variables.)

Later,

K

[ttrigg]

Go to you nearby fisherman’s store. Pick up a fish weight scale. Drive a spike in the ground attach the handle of the scale. Tie a cord to the tender and tie to the "fish hook". Apply power and watch when the wheels start to spin.

[cabbage]

Well the cheapest is often the best... A simple spring balance will give you the tractive effort of your locomotive. The "Greenly Formulae" will give you a working number for your tractive effort without using a balance. Thus for each 1,000 Grammes of loco weight a maximum of 230 Grammes of that is available for tractive effort. This is reduced by bogie wheels and idler wheels. regards ralph

[trainguy111]

Hello! I recently purchesed a Lionel Gold Rush Special set from ebay. I would like to measure its drawbar pull. Does anyone know what Garden Railways uses for its reviews, and how much it costs? And does anyone know if there are any similar measuring devices for a reasonable price?