What is a practical limit to how many cars can be pulled in single-engine consis

Started by Neo Fender, January 12, 2009, 09:30:35 PM

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Neo Fender

I understand there are other factors such as # of turns, radius, length of track, etc.  I have entry-level locomotives (FT-A and a GP40) and I'd like to get more rolling stock.  Just looking for a general guideline.

Thanks.

Yampa Bob

My Bachmann FTA and GP40 each have a drawbar force of about 4 ounces on level track.  If your cars are fine tuned by reaming the journals and using metal wheelsets, they should require only .08 to .1 ounce of force each to pull them.  Dividing 4 ounces by .1 equates to 40 easy rolling cars before stalling. (wheels slipping)  Your performance may vary.

As a general rule of thumb, start with 15 to 20 easy rolling cars for a stock single loco to attain a realistic speed.

I make my own force gauges, but here is an inexpensive ready made. I think it's a must have for tuning your loco and rolling stock. The 250 gram (8.75 ounces) is adequate for HO scale.

http://www.delta-education.com/productdetail.aspx?Collection=Y&prodID=1973&menuID=
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

Jim Banner

Around 20 freight cars.  More on straight track.  Less on grades.  But 20 cars would be a train about 12 actual feet long, which is pretty long for a small layout
Growing older is mandatory but growing up is optional.

Atlantic Central

This depends a lot on the engine and the cars.

My Broadway Limited N&W class A (2-6-6-4) easily pulls 75 average cars.

Sheldon

Woody Elmore

Asking how many cars in a train is like asking how big is a dog. There was a railroad here in NY State, the New York Ontario and Western, that went belly up a half century ago. There is a picture in Helmer's book about the railroad  showing the road's FT ABBA lashup pulling three cars!

pdlethbridge

I used to have a formula  for car capacities on locos. Rather simple and it allowed for grades
1 passenger car for each drive axle and trailing truck axle This gives a good look and good load for any engine. A 4-4-0 would have 2 passenger cars, 2-6-0 -3 cars, 4-6-2 would be 4 cars, etc
For freight cars it would 1 1/2 cars per axle plus caboose rounded up. The fomula isn't perfect, but it does provide some basic guide lines for operation. With tight curves, steep grades, scenery brakes, a short train would be great

Johnson Bar Jeff

Quote from: Jim Banner on January 12, 2009, 09:51:53 PM
Around 20 freight cars.  More on straight track.  Less on grades. But 20 cars would be a train about 12 actual feet long, which is pretty long for a small layout

That's the way I usually approach the question, how long a train looks good on my layout rather than the mechanical capabilities of the locomotive. If your layout is small, you don't want to watch your engine chase its caboose or ETD like a puppy chasing its tail.  :)

SteamGene

If you have several sidings for industry, switching adds to the number of cars on the layout, but not the number in the train. 
How large is your layout?
Gene
Chief Brass Hat
Virginia Tidewater and Piedmont Railroad
"Only coal fired steam locomotives"

Neo Fender

It's approximately a 7.5' x 3.5' kidney shape with a passing loop and a siding that branches into two sidings.  Don't know the total track length.

Quote from: SteamGene on January 13, 2009, 03:12:04 PM
If you have several sidings for industry, switching adds to the number of cars on the layout, but not the number in the train. 
How large is your layout?
Gene

Running Bear

I generally limit the # of cars to 12 for one loco. If you look at prototype practice it's usually the same. You have to consider the long term wear and tear that pulling a long cut of cars is going to put on the loco. A loco pulling 24 cars looks real good going around the layout but what's happening on grades, on curves and through turnouts. Going up a grade or around a curve slows the cars down as does going through a turnout. This increases the amount of weight the loco is pulling and puts additional stress on the drive train. I've seen locos that have sheared the ends off the drive shafts because of too much weight. What does the modeler do? Puts in a heavier shaft of course. Next to go is the motor or the decoder. Here's the way I handle it. 1 loco = 12 cars, 2 locos = 24 cars, 3 locos = 36 cars, etc. While 3 locos can pull more than 36 cars I err on the side of safety rather than high maintenance.
Running Bear

SteamGene

On a layout that size I'd want small locomotives and small trains - reference the dog chasing his tail comment above.  Five or six cars should be about right, even if it is a large articulated.
Gene
Chief Brass Hat
Virginia Tidewater and Piedmont Railroad
"Only coal fired steam locomotives"

Pacific Northern

Quote from: Neo Fender on January 12, 2009, 09:30:35 PM
I understand there are other factors such as # of turns, radius, length of track, etc.  I have entry-level locomotives (FT-A and a GP40) and I’d like to get more rolling stock.  Just looking for a general guideline.

Thanks.


How large a layout do you plan on having when completed?
Pacific Northern

Neo Fender

Not much larger :(.  I still have two G (large) scale and two O scale trains that I need to get up off the floor.

Quote from: Pacific Northern on January 13, 2009, 06:49:18 PM
Quote from: Neo Fender on January 12, 2009, 09:30:35 PM
I understand there are other factors such as # of turns, radius, length of track, etc.  I have entry-level locomotives (FT-A and a GP40) and I'd like to get more rolling stock.  Just looking for a general guideline.

Thanks.


How large a layout do you plan on having when completed?

lmackattack

On the large club layout with easy grades and radius
my bachman Mountain can pull about 35 cars
Blueline heavy Mikado(traction tire) can pull 48
Broadway Mikado pulls 32
IHC Hudson pulls 32
GP18 pulls 38
proto 2000 SD9 48 cars


On my home layout with 3% grades and 22" radius
the Bachman mountain pulls 14 cars
Blueline heavy Mikado(traction tire) can pull 20
Broadway Mikado pulls 10
IHC Hudson pulls 10
GP18 pulls 13
proto 2000 SD9 22 cars

It really depends on the loco and layout conditions. if it has tires, track radius, grades etc... I have seen Bigboys pull 120 car trains with traction tires/without tires 80 cars

Trent



Tylerf

on our club layout we recently got 129 free rolling coal cars pulled by 2 Athearn Genesis SD70s and one SD70 on the rear. the minimum radius curve was 45 degrees.