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How Much Can A Loco Pull?
Don asks readers:
“The grade calculator at http://www.modelbuildings.org/free-calculator-tools.html was great thanks. What I need most is what is the most grade an HO engine should pull ( ballpark )”
SUBMIT YOUR QUESTION
No steeper than it can manage with the number of vehicles in tow that you wish to have. Personally, I prefer to see no more than about 1:50 (2%).
a can of worms. I have 3% compensated. I normally run 2 powered units. My club layout has 1.5 and 2% grades 3 6 axle units will handle 75-90 cars. steam, most 4 axle diesel will pull m
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Maybe the question should be “How much should a loco pull?
The answer lies in its prototype. A loco that spent its life shuttling between stations and halts with 2 passenger carriages should be emulated like for like. Our 1:87 0-6-0 might pull 20 coal wagons, but should it? Your full sized “Bigboy” could pull 100 hoppers over the Sierra’s, so your 1:87 version should too. Research your fvourite prototype railway and follow its lead. As for grades, keep under 3% if you can.
How much a loco can pull depends on the loco. We each have different ones so YOU try with the ones you have to test it yourself on your layout.
That’s about the size of it.
The best way is for you to try it at home on your layout. That way you will know for sure.
Try it.
The maximum gradient slope will depend on:
1) the traction of your locomotive,
2) the weight of the train it has to pull.
Weigh your locos and rolling stock. Measure the useful loco traction by the force needed to just slide it along a level track with the power off.
( I do this with small weights on a thread running over the edge of a table.)
Then calculate the total train weight the loco can pull up a certain slope using the principle of the inclined plane. (Get out your School Physics Textbook !)
(But any track curvature adds friction, so will make it a bit less.)
“The mechanical advantage of an inclined plane, the factor by which the force is reduced, is equal to the ratio of the length of the sloped surface to the height it spans.”
(https://en.wikipedia.org/wiki/Inclined_plane)
Loco traction can be increased by weighting the loco with lead, available as sheet or shot (or just lengths of solder).
Unfortunately, my school physics class (curtailed at age 14) covered only heat, optics, electrics, density & levers, so a translation would be helpful.
And we didn’t have text books before the 6th Form.
Richard H says : I had some problems with One of my slope sections of track. I tried putting the rubber bands that are supposed to help on the wheels that worked OK on N scale but did not work on my new HO scale.
I’ve had the most luck by cramming in as much weight as I could to the locomotives by removing the cover and adding weights. This solved my problem.