# PULLING POWER



## Festus (Jun 28, 2010)

I hope to have 5 or 6 trains on my mainline. All five sidings are at least 25 feet long. That ought to allow a pair of diesels and 15 cars, or my 2-8-8-2 and 15 cars. Attached below is a partial list of the largest diesels I have to put on the mainline. Not all will pull 15 but I'd like that to be the standard. Does anyone see any problems with any units on the list as far as getting the job done with 15? Also, I'd like to have a few pull 25 or more alone on the mainline. How many will be able to do that? Has anyone done any tests with their 2-8-8-2 or any others on my list to see just how many they can pull on a level surface? 

ARISTO-CRAFT RS-3 AM TRAK USA UNION PACIFIC NW-2 ARISTO-CRAFT UNION PACIFIC FA-1 ARISTO-CRAFT UNION PACIFIC FB-1 ARISTO-CRAFT UNION PACIFIC FB-1 ARISTO-CRAFT *#22605 SANTA FE CENTER CAB DIESEL* ARISTO-CRAFT ROCK ISLAND U-25B DIESEL ARISTO-CRAFT SD45 #5450 SANTA FE USA NW-2 CALF LIONEL GP-20 UNION PACIFIC LIONEL GP-20 UNION PACIFIC (DUMMY) LGB GREAT GEORGE & BOULDER 0-4-0 DIESEL ENGINE ARISTO-CRAFT #22318 NEW HAVEN FB-1 ARISTO-CRAFT #22018 NEW HAVEN FA-1 ARISTO-CRAFT #22018 NEW HAVEN FA-1 ARISTO-CRAFT # 22103 NEW HAVEN U25-B USA SANTA FE 20 TON SWITCHER LGB #2060 SWITCHER ARISTO-CRAFT #22103 NEW HAVEN U25-B MDC #G2110 0-4-0 BIG HUSTLER SWITCHER *LGB* *#2061 SWITCHER* ARISTO-CRAFT #22004 SP FA-1 ARISTO-CRAFT #22054 SP FB-1 ARISTO-CRAFT UNION PACIFIC FB-1


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## chuck n (Jan 2, 2008)

Another factor in pulling power to consider is the diameter (radius) of your curves. Tight curves will significantly reduce your apparent pulling power.

Last Friday afternoon I was out at Dr. Rivet's layout with my Aristo 2-8-8-2. I had it pulling two trains. The first was with 10 USAt streamliners and the second was a freight with 38 cars. There is a 0.6% grade on this layout. I have also pulled a train with 32 iron ore cars on this layout with the Mallet. As far as anyone could tell the engine didn't have any problems on the grade or anywhere else on the layout.

The engine was powered by battery and Aristo's REVO. Pulling those loads I got at least 3 hours before I had to swap out the battery pack. Special thanks to Stan Cedarleaf for suggesting a second pack.


If you go to this thread and scroll down to Scott McDonald's contribution on May 18, you will see the Mallet in action with the 32 car ore train, one box car (with battery and REVO) and a caboose in tow. All the cars have metal wheels, so there is a lot of weight to pull around.


Mallet with 34 cars. 

Chuck


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## Festus (Jun 28, 2010)

The curves on my mainline will be 15' and 8' but nothing smaller. Hopefully this will help. As I purchased the diesels, I was never able to find any info on pulling power, I just trusted Aristo-Craft because they were so popular with everyone else. And since I was a Lionel guy in O scale my entire life, I had to try one of theirs in G scale just for comparison. Same with USA. I heard they draw a lot of power. It'll be fun to see. I'll check out the video. Hopefully the stuff I bought will do the job. I can't afford anything bigger. The 2-8-8-2 was a gift from my family. Bachmann is cheap, but I read a lot of articles about modifications people made to improve their pulling power because it was practically nonexistent, but never about any other brands. So I'll be modifying my Bachmann 2-6-0's ASAP; adding weight, but I doubt they'll be able to pull 15 no matter what. We shall see. Lots of fun at any rate. What's the record for Bachmann 2-6-0 pulling power. Anyone tried to set one? Festus


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## chuck n (Jan 2, 2008)

Your dual motor engines should be able to pull 15 cars. If you use FA and FB lash ups you definitely will be able to pull 15 cars. Your single motor engines may not. 

Are your 15' and 8' curves diameter or radius? 15 cars on 8' diameter will have a lot of drag.

Chuck


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## krs (Feb 29, 2008)

Has anyone tried to increase the weight of USA Trains or Aristocraft engines to increase their pulling power? 
For LGB engines we do that routinely since their motor blocks, gears and motors can handle that without problems, don't know if the same is true for USA Trains and Aristo engines. 

One other thing that affects pulling power greatly and is not often thought of is the weight distribution of the particular loco. Sometimes manufacturers don't take that into consideration. 

Knut


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## Ted Doskaris (Oct 7, 2008)

On my layout one Aristo RS3 (older type, non ball bearing type trucks) could pull no more than 17 cars before its wheels would noticeable slip. (That's before I added 20 oz of weights in the fuel tank - afterwhich it could pull 21 cars.) 

My under house layout is level but fairly circuitous, includes mostly 10 foot diameter curve tracks and a few “S” bends. The longest straight track section is about 8 feet. 

As others have pointed out, for layouts being less circuitous or for layouts with tighter curves and grades, they will have more or less results with respect to the amount of cars that can be pulled.

See below article title:
"*Aristo RS3 loco weights Vignette*"


As to effects of wheel drag (and improvements) on curves, I did some tests on this issue some time ago using Aristo freight trucks.

See below article title (Scroll about half way down to "Freight truck wheel / axle skew and drag issues"):
'*Aristo-Craft Metal Wheel "train accessory" kits and wheel issues*' 

-Ted


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## aceinspp (Jan 2, 2008)

Each of the locos that you have listed all have different pulling capacities. Not nessarley based on curvature as the locos them selves are limited by design and wheel arrangement and weight of each. From there then one can calculate what each is capable of handleing. Later RJD


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## Festus (Jun 28, 2010)

The curves mentioned are diameter, not radius. I'll have four "corners" of 15' diameter, an S curve filled with 8' diameter and that's about it until I get to my 2nd railyard. All the sidings will be the 16000 series LGB, or 8' diameter curves. Access to my main railyard will be through 18000 series LGB switches, or the 15' curves, in and out. It sounds like it'll be "by guess or by gosh" with which will pull how many cars. I planned on doubling up my diesels to help out from the start. If anyone has any additional articles on adding weight to my diesels/locos, let me know where the articles are. Also, an article on weight distribution of locos mentioned. Has there been an article published? I thank you all for your input. Festus


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## W3NZL (Jan 2, 2008)

*If U really want to know how much TE (tractive effort) an engine has, U need *
*to remove the ambiguity from test, to say any given engine will pull X number *
*of cars doesn't mean much, whose cars, what kind of track, have they been lubed *
*lately, etc, etc... If U really want to know what the TE for any given engine is, then *
*U need to build a TE dyno, something like the one pictured below, I built it *
*several years ago, its fairly simple and easy to put together, and it removes all *
*the ambiguity from the test, each engine undergoes the same test... U get the *
*results in lbs & oz too... with pictured ammeter in line U get the current draw *
*as well... OR, in the case of a typical engine, on the typical layout, **U can take *
*15-17% of its weight and **that will be about what its TE will work out to be... Very *
*few will exceed that by much, unless its equiped with traction tires, an if the *
*tires R clean, they'll go as hi as 30% of the weight... The unit will dispel some of*
*the common myths, an old wives tales about TE too... *
*Paul R...*


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## krs (Feb 29, 2008)

I built a similar contraption to the one above but to measure how much force is required to move the various cars, specifically testing the drag of various ways to pick up power for lighting. 
My set up was temporary and made from things I had - a three foor section of track - a pulley and means to fasten it to the track all made from Lego parts - and the string went over the top of the pulley and down over the edge. 
I added weights until the car moved and then measured the weight on a digital scale. 
I was surprised by the variation of the drag of the different cars. 

To measure tractive effort, I went out and bought a digital "fishing" scale for $10.- like this one: 
http://www.dealextreme.com/p/digital-hanging-scale-1164


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## Greg Elmassian (Jan 3, 2008)

All good advice so far, although as many people have stated, the layout is a huge variable that is pretty hard for people to quantify, grades, the curves (S curves are worse than a single 90 degree one, etc.) 

Another factor is the type of rail... stainless is much more slippery than brass in my experience. I know from other threads that you are track power, so you will be dealing with "clean" rail... Some of the best traction comes from oxidized aluminum rail, then followed by brass, because the surface has more "bite"... just an example. 

But to answer the original question, you have a wide range of locos there... the switchers would probably strain to run 15 cars... 

What's the criteria? You have to make all trains 15 cars? Then you may have to double up on some locos, or maybe even go to something extreme like ball bearing wheel sets on all rolling stock. 

I think you are worrying too much. Design the layout with the broadest curves, "smallest" grades, and eliminate as many S curves as possible, and make the curves the least "degrees" you can. 

Now that you have done the best with your track, start checking your locos out. Some may just be too small. Since you already have them, it's pretty much a moot point if there is no way to cut it. 

Yes, you can add weight to USAT locos, there's other factors to consider such as traction tires, sliders, etc. 

I'd build the layout first, and handle your other larger problems, like your Marn-O-Stat controls that you want to use. 

Regards, Greg


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## Festus (Jun 28, 2010)

One last thing now. Can someone tell me how to build a TE machine? Or send the website where the instructions are? THANKS FESTUS


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## Totalwrecker (Feb 26, 2009)

You've mentioned having S curves, common practice is to have a length of straight track equal in length to your longest loco or car , between the two curves. This eliminates binding at the couplers... 

John


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## W3NZL (Jan 2, 2008)

*Festus, *
*The thing pictured above is something I concocted on my own some years back,*
*it really is as simple as it looks though, a vertical scale transitioned to work *
*horizontally...* *I have no idea if there is any info online on how to construct one or 
not... Its made **from some hi-dollar materials that I happened to have laying around, 
and I would **not recommend that anybody go out and buy the stuff new thats in it 
at today's prices, thats a legal for trade scale U see in the pic, **it'd probably cost $125 
for the scale head alone at today's prices, an U don't need finished white oak rake 
rail for the frame either... just ain't worth it for the use **it is... U could build something 
that would work for probably $25 that would work **almost as well... I originally ran the 
idea by the **guys over in the weights & measures div at NIST, they thought it'd work 
fine, **just be sure to keep the scale **in a vertical, "hanging" position and transition **its 
action to horizontal, so I did with the ball-bearing pulley arrangement.... I'd be happy  to answer any specific ? U might have about it...
*
*Paul R...*


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## chuck n (Jan 2, 2008)

Festus:

If you have any children or know any children of friends who are in middle or high school, this would be an interesting science fair project. A successful project would help all of us.


Chuck


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## chuck n (Jan 2, 2008)

I just went out to my fishing equipment, my other hobby is fly fishing, and got out my fish scale. I wanted to see if it would work in measuring tractive effort and pulling resistance. I wrapped a string loop around the coupler of the tender on my Bachmann K27 and hooked the other end of the loop on the fish scale. The wheels started to slip at between 3.5 and 3.75 pounds. I also used this system to check on the drag on a NG freight train. The train had 10 Accucraft cars: 6 box cars, 2 reefers, one of the new combines, and a short caboose. On straight level track the drag was about 2 lbs, and on a 10' diameter curve the drag went up to 2.5 lbs.

I don't know if it would make any difference or not, but this engine has Rodney's new gear system. My guess is that engine weight and wheel material is more important than the motor and gears. 


This was measured on LGB brass sectional track. 


Here is a picture of my high tech system.










I'll try it with the Aristo Mallet the next time I have it out.


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## Axel Tillmann (Jan 10, 2008)

I became curious about the impact of addition weights and traction power too so I bought spring scales from a school supply store (enasco.com) for $3.50 - $4 per weight range. At that price I bought a few becasue little switchers don't have as much pulling power so I wanted a finer reading.

Here is one example:


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## aceinspp (Jan 2, 2008)

Just remember all test for pulling capacity is done on straight and level track same for the 1 to 1 RR. So once determined on the geometry of the RR that is what determines when to add additional locos. Thats how the big boys do it. Later RJD


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