# Weight on non driving wheels and pulling power



## chuck n (Jan 2, 2008)

I originally posted this in Devon's thread. Rather than derail his thread, I'm starting a new thread.

The text below was posted in his thread.

I now know why the USAT Hudson has such poor tractive effort when compared to my other engines. I just measured the weight on the leading truck and the trailing truck.

The engine weighs 25 pounds. Here are the weight on the track of each of the trucks.

weight on track of front truck 2.72 pounds (11% of total weight)
weight on track of trailing truck 6.12 pounds (24.5% of total weight)

That means that only about 16.16 pounds of the engine weight is on the drivers. That brings it up to about 31% without the leading and trailing trucks. That is a value that is consistent for most of my engines.

To make the measurements, I used a kitchen scale with a piece of track on it. I measured the height from the table top to the top of the rail. I then put another piece of track on the table and built it up until it was level with the stop of the rail on the scale. I put the trucks on the scale track and the drivers on the table track.










I think that the springs used to push the trucks down on the track are a stiffer than those used on many other engines. Sometime I'll try this with the GG1.

Thanks David for giving me the idea.

I had no idea that much of the engine's weight was being supported by the leading and trailing trucks.

Chuck

New information.

I have now measured the weight distribution for several other engines, using the same setup pictured above.

Here is my latest tractive effort table with just total engine weight.










Here is a table with the weight on the leading and trailing trucks of some engines.










I now know why the Aristo Mallet is such a great puller. There is very little of its weight on the leading and trailing trucks.

Chuck


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## Jerry McColgan (Feb 8, 2008)

Hi Chuck,

Great Information! Thanks for posting it.

One thing that comes to mind is LGB Moguls vs LGB Forneys.

I was always told an LGB Mogul would out pull an LGB Forney. I tried it and it was true but there was a side effect.

The Mogul lost tractive power because the spring in the pilot truck pushed up reducing the downward pressure on the drivers. When compared with the 2-4-4 Forneys like the DRGW 25251 the Moguls definitely had less traction but the LGB Moguls will push through a turnout thrown the wrong way while an LGB 2-4-4 Forney will frequently derail on the same turnouts.

Bachmann Ten Wheelers would frequently derail on my turnouts because there was no spring to push down and through turnouts (others added weights to their pilot trucks).

Yours is the first serious effort to provide information of G Gauge pulling power.

Thanks to Ray Manley I know the MTH Challengers and Big Boys have great pulling power.

Cheers,

Jerry


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## chuck n (Jan 2, 2008)

Jerry, my Forney is an early version. It doesn't have pilot trucks. It has the highest percentage pulling weight of any of the LGB engines that I measured. I have always been disappointed in the tractive effort of the LGB Moguls.

I have some engines that will easily go through closed switches and pop the switch and some have pilot trucks that derail. Perhaps I'll start keeping a record of those that have a problem and those that don't. My nonscientific memory is that LGB engines don't have a problem, but I can't remember the ones that have a problem.

It will be interesting to see the weight on the leading trucks for the engines that derail.

Chuck


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## Semper Vaporo (Jan 2, 2008)

One of my Aster Mikes had a problem with the pilot wheels derailing. Rather than increase the spring's strength in pushing them down, which would also result in an equal push UP on the front of the boiler (which the Aster Mike already seemed to have a look of the front being too high), I added a pound of lead weights to the truck itself to let gravity hold it down. This added one pound to the total weight of the engine, but did not subtract any weight from the drivers. And the wheels no longer derailed. (My other Mike did not exhibit the problem, so it is unmodified.)


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## chuck n (Jan 2, 2008)

SV

Neat idea. Add weight to the truck and not add a stronger spring.

Chuck


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## Dan Pierce (Jan 2, 2008)

LGB moguls have a spring loaded center axle and would give very little traction plus it gets its power from the plastic side rods, not from a gear.


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## chuck n (Jan 2, 2008)

Dan

Looking at the mogul when I place it on the track, the center driver moves up when the last pair of drivers is placed on the track.

Therefore, it is helping. It may be less than the front and rear drivers, but it is still helping drive the engine.

Chuck


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## JackM (Jul 29, 2008)

*what is "it"?*

Please forgive my denseness, but what is the "it" in the last two columns of the first chart (with it, without it)? I've re-read the post a number of times, but can't find the association.

JackM

I am prepared to have a "D'oh!" moment.


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## Ironton (Jan 2, 2008)

Jack,

The IT refers to having traction tires on one or more of the drivers. Compare the last two columns to the number of traction tires column.

Hope this helps.


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## chuck n (Jan 2, 2008)

It is "tt" for traction tires. Between scanning the table and reducing it's size (to 800 pixels) it lost some resolution. It shows up as "tt" on my screens.

Chuck


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## Jerry McColgan (Feb 8, 2008)

Hi Chuck,

I may have missed it but how did you measure the pulling power (lbs)?

Thanks,

Jerry


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## chuck n (Jan 2, 2008)

Jerry

I discussed my methodology back in 2011 in a thread by Festus, which I can't find. Some how search my posts only goes back 500 posts.

But basically I used my fisherman's scale. I hooked it to the engine with a piece of string and then increased the voltage until the wheels slipped.

Chuck

If the wheels don't turn, you get about the same weight by just pulling the engine.


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## chuck n (Jan 2, 2008)

If any of you have a son, grandson, daughter,or granddaughter, I think that a systematic study of the tractive effort on our engines, would be a great science fair project. If they could affiliate with a local club, there would be a lot of engines for a very valuable database.

Just a suggestion.

My attempts haven't been that rigorous, a systematic study might bring a lot of useful information.

Chuck


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## Jerry McColgan (Feb 8, 2008)

Hi Chuck,

I thought I remembered a fishing scale.

Thanks,

Jerry


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## chuck n (Jan 2, 2008)

It worked. There are probably better scales, but that is what I had. It was graduated in 0.5 pound intervals, non digital.

There are now digital scales that have more refined measurements. If someone wants to give me one , I'll redo the measurements.

CHUCK


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## Pete Thornton (Jan 2, 2008)

chuck n said:


> It is "tt" for traction tires. Between scanning the table and reducing it's size (to 800 pixels) it lost some resolution. It shows up as "tt" on my screens.
> 
> Chuck


Chuck,
This new forum s/w lets you upload a large photo. It posts it as 800x600 but there's a banner at the top saying 'image reduced, click here for the original' or something similar. You click and see the big version.


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## Greg Elmassian (Jan 3, 2008)

Chuck, I don't have your private email address, wanted to discuss something with you, can you email me?

(I cannot pm you since I have PM off myself)

Thanks, Greg


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## chuck n (Jan 2, 2008)

Greg

Message sent 1600 this afternoon. I've been having email problems today. Let me know if it didn't arrive.

Chuck


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## chuck n (Jan 2, 2008)

Pete

Thanks for the information, unfortunately, my MLS space is getting full and I need to reduce the size to have room for pictures. I should get rid of a lot of old pictures, but which ones, and it is a Pain In The A..., deleting one at a time.

Cheers,

Chuck


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## riderdan (Jan 2, 2014)

chuck n said:


> Pete
> 
> Thanks for the information, unfortunately, my MLS space is getting full and I need to reduce the size to have room for pictures. I should get rid of a lot of old pictures, but which ones, and it is a Pain In The A..., deleting one at a time.
> 
> ...


One of the disadvantages of deleting photos (for the rest of us) is that a lot of old threads become significantly less useful without the images. I can't count the times I've found an old thread on a message board that says something like "you can see how I did it in this picture" next to an "image not found" icon.


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## chuck n (Jan 2, 2008)

I understand that, which is why I don't like to do it. The ones I have deleted, are ones that have little value, I hope.

But I'm running out of space. Any ideas on how to increase space without opening an account in a cloud.

Chuck


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## Totalwrecker (Feb 26, 2009)

Well you can add pics as attachments straight from your hard drive.
The dance invite is the box below the Quick reply message box that reads Go Advanced.
Click that and scroll down to the box 'Manage attachments'. Browse your files add up to 8 pics, upload and close box and there you go. Does Not require any online space by you. 

John


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## chuck n (Jan 2, 2008)

Thanks John. I'll have to try it.

Chuck


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## chuck n (Jan 2, 2008)

John

I just tried it. It works! See HH's engine house thread.

Thanks, it is a lot easier.

Chuck


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## Totalwrecker (Feb 26, 2009)

Rest in peace my friend, we're gonna miss you this spring...








I was trying to get JJ too, but you have to be real quick to steal his soul....

John


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## fyrekop (Sep 20, 2011)

John,
That would have been a great photo since you got Dirk in the far background tool. That was a good day and Chuck will be missed.


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## SD90WLMT (Feb 16, 2010)

Chuck is definitely missed by US all.. Springs a comon.. take a lap in his Honor perhaps in order!

Thanks Guys
SD

Btw.. I sent Nancy a sympathy card after my trip to CA.. signed in All Our Behalfs...!
Amen Brother..


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## Totalwrecker (Feb 26, 2009)

Thanks, bro, 
I was thinking of her as I posted the above....

yer bud,
John


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## Dan Pierce (Jan 2, 2008)

The oldest LGB moguls with 2 traction tires will pull more than the Forney, but these I believe were the early 1990's manufacture. Rest of the Moguls have only 1 traction tire.
Also, older LGB engines had lead weights, newer ones are lighter with lead free cast metal weights.


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## rdamurphy (Jan 3, 2008)

I would be curious to see the results from a K-27 and a C-19...

You could go one step further:

http://www.republiclocomotive.com/locomotive-power-calculations.html

Robert


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## SD90WLMT (Feb 16, 2010)

As TW alluded in post #25, I read that Services for Chuck will be in the Spring. No dates yet! 

SD


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## East Broad Top (Dec 29, 2007)

The C-19 pulls right around 2 pounds.

Dave Goodson's review of the K-27 lists its drawbar pull at 2.5 pounds.

Later,

K


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