Boosting Tractive effort

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phils2um

Phil S
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Hi Folks,

I don't know whether this particular solution has been mentioned here before.

My LGB crocodiles and and Ge 4/4 II loks were having trouble pulling the desired consists of 6 four axle passenger cars (3067 and similar) up the 3.5% grades on my layout. They would handle 4 cars, but any more resulted in wheel slip. I actually wore through a crok's traction tire one afternoon trying to pull the 4 Alpine Classic Pullmans and matching baggage car around the layout.

This is what I did to increase the locomotives' tractive effort. I added some weight using 1 lb. bean bag type scuba dive weights. After experimenting by placing the weights on top of the loks and running them up the grades, I found a total of 3 lb. additional weight was satisfactory for my needs. I could stop a consist on the grade and resume the uphill climb with minimal to no wheel slip. I was able to acquire the weights on EBAY for $4 each which I thought was quite reasonable.

I covered the mesh bags with duct tape before "permanently" installing then. This was to keep the lead shot from shorting any electronics the bags might contact. The Ge 4/4 IIs were easy. There's plenty of room inside the lok's body to hide the weights. The Croc's were another matter. But, I did find a 1lb. bag fit well under each hood on top of the existing weight. The third lb. was put in the cab over the hood end that has the traction tire. I fit nicely and is below window height so doesn't stand out. The only drawback is the door wont open with the weight in place.

Phil S.
 
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A bit of weight often helps - but be careful not to over do it, or you will be needing new motors and gears. Can your locos still spin their wheels if necessary or does the motor stall - if the later, you are asking for trouble.
3 pound sounds a bit near the limit of mechanical sympathy to me.
 
Hi Alan,

A good point. I had not thought about the motors stalling (and burning up!). But, the loks will still spin their wheels with the the 6 wagons and some additional drag applied. That's actually where my 6 passenger car limit came from. I will admit to being a little concerned about the additional wear and tear though.

Phil S.
 
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Hm me thinks that the Gradient is too steep. What about adding a Banking Loco to the consist for just that section? Will add a little of interest to the Operation.
JonD
 
That's quite a bit of weight you've added, Phil. I can't say that I agree with adding that amount to a loco, even a large one like a croc. Your loco may pull the consist you want it to handle but I would be concerned not only about motor burnout but also of gear damage.

Double heading would be my preferred method of handling heavy trains.
 
As previous posts, I'd be very careful, LGB would have done a lot of testing whilst designing their locos to find the best motor/gearing/weight/traction ratios. To try and drastically alter that is truly asking for trouble.
 
I have a 10% (1:10) max gradient on my layout and, when hauling a weighty train, I use multi heading or 'motorised' rolling stock (passenger or freight cars that have been 'invisibly' given a motor bogie to replace a passive one).

When hauling a rake of 6 or so of non-motorised heavy aluminium Aristo craft or USA Trains streamline cars (which are generally my heaviest trains) I hook up three or four USA Trains F3 units or a twin set of PA1/PB1. These have rubber tyred axles.

I also have two LGB Amtrak Genesis locos and they can haul six LGB 'metro' coaches together with one Aristo aluminium streamline baggage car up the incline. They would sometimes (depending on the weather conditions (damp track etc) and whether there is a bit of crud on the track, spin their wheels at the place where the gradient is at its max. I have put a little extra weight (about a couple of pounds split for both ends) in both locos and they no longer spin their wheels when hauling the same load.
I have not tried adding extra coaches above the seven.

The freight trains (up to about a max of 14 cars) are multi headed with up to three or four locos with one of the very slightly 'slower' ones at the rear to act as a 'dynamic' brake when going down the gradient to stop the weight of the cars causing problematic forces causing derailment.

If I want to have just one or two locos with a fairly decent rake of freight cars, then I use up to three 'motorised' freight cars dotted amongst the passive cars.

11 years on and no split gears on any of my locos (and that also includes my steam locos).

Now, in case someone on this forum, and they know who they are, dives in to tell me off for maybe encouraging people to do the same, I will put a disclaimer... I have tried this and it works for me and has not caused mechanical grief, but I am not advising that the practice is not without its risks....... I have found out the best combination of power to overcome my gradients through trial and error trying out different placement of locos to do the work and to 'balance' the complete train. Sometimes even the placement, in a train, of particular cars would cause a problem on the downslope due to their couplers, bogie specifications etc.

One thing that I will say is that if you are going to haul a heavy train up a large gradient, then the strength and ability to remain 'clenched' of the couplers plays an extremely important role if you do not want run-aways!

My couplers:
The USAT aluminium streamline rake uses the built-on metal USAT knuckle couplers ( these are the only USAT couplers that I will use as the plastic ones have never worked well for my particular needs).
The Aristo aluminium streamline rake uses the built-on Aristo knuckle couplers
The LGB Amtrak streamline rake uses built-on LGB knuckles
The Bachmann Jackson Sharpe coaches use Bachmann knuckles
The LGB Jackson Sharpe closed and unclosed vestibule coaches use Aristo or Bachmann knuckles
My freight rakes use either all Aristo knuckles or all Bachmann knuckles
Occasionally I will run freight with a mixture of couplers.
I have also run freight trains with all hook and loops (with both hooks at either end of a car).

I have found the best couplers (though not prototypical in size) to be the Aristocraft ones.
Not only are they strong but they have an inbuilt non-ride up design, (they do not slip up or down), that is really useful if there are any peaks or troughs in your track (yes, I know there shouldn't be). They are also great when put under pressure on downslopes.
I will eventually change all the LGB couplers (both knuckles and hook 'n' loops to Aristo.

I have not included my Fn3 (1:20.3) locos or rolling stock in this post as they operate on a different basis on my layout.
 
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Yep, 4 locos sounds right, my concern was a single loco.

Gears are cheap, so try it with the extra weight. I have steep grades, and I have added weight to my Aristo diesels, but they all have the "prime mover" motor blocks, which have huge gears and ball bearings.

prime_drive.jpg

prime_gears.jpg

prime_worm.jpg


But on USA trains, the chassis is supported by plain bearings in the journals, and even without extra weight they wear. There are people who have fitted ball bearings.

On LGB, many people have had no issue with their products, well built, but many have had issues trying to make them heavy duty pullers.

So my post on the GG-1 was to tread carefully.

Greg
 
Hi Greg and Others,

Here are the before and after weights of the 4 locos to which I've added the lb's.

LGB 2040, Original Brown Krokodil (My first LGB purchase made on a 1984 vacation in Austria/Germany/Switzerland.)
Loco: 3.24 kg, loco w/added weight: 4.15 kg (2 lb.)
Note: no room under the hoods of the original 2040's but plenty of space in the body unlike the newer versions.

LGB 27402, Blue 75 year Glacier Express, Bemo, LGB Krokodil
Loco: 3.80 kg, loco w/added weight: 5.17 kg (3 lb.)

LGB 28438 and 28440, RhB Ge 4/4 II's
loco: 4.43 kg, loco w/added weight 5.79 kg (3 lb.)

I may cut the added weight down to 2 lb. for the latter three locos. 20 to 30 percent more weight does not seem unreasonable to me so long as it can not cause the motors to stall when pulling a full consist. It turns out that the location where I was having the worst problem has a much steeper grade than the 3.5% of my "grade gage". I thought I had fixed the long climb but, it needs more work near the top!

I think these particular locos should be able to handle five to six 4-axle wagon consists without a helper on my line just like the originals. Helper locos are nice. Some of my other locos will need them for a long train and the interaction required can be fun. Sometimes, though, I just want to enjoy watching the trains go round.

Phil S.
 
phils2um said:
Hi Greg and Others,

Here are the before and after weights of the 4 locos to which I've added the lb's.

LGB 2040, Original Brown Krokodil (My first LGB purchase made on a 1984 vacation in Austria/Germany/Switzerland.)
Loco: 3.24 kg, loco w/added weight: 4.15 kg (2 lb.)
Note: no room under the hoods of the original 2040's but plenty of space in the body unlike the newer versions.

LGB 27402, Blue 75 year Glacier Express, Bemo, LGB Krokodil
Loco: 3.80 kg, loco w/added weight: 5.17 kg (3 lb.)

LGB 28438 and 28440, RhB Ge 4/4 II's
loco: 4.43 kg, loco w/added weight 5.79 kg (3 lb.)

I may cut the added weight down to 2 lb. for the latter three locos. 20 to 30 percent more weight does not seem unreasonable to me so long as it can not cause the motors to stall when pulling a full consist. It turns out that the location where I was having the worst problem has a much steeper grade than the 3.5% of my "grade gage". I thought I had fixed the long climb but, it needs more work near the top!

I think these particular locos should be able to handle five to six 4-axle wagon consists without a helper on my line just like the originals. Helper locos are nice. Some of my other locos will need them for a long train and the interaction required can be fun. Sometimes, though, I just want to enjoy watching the trains go round.

Phil S.
Click to expand...
Poor locos, are you sure you are not going to burn them out?
 
Hi Paul,

I had the 2040 running around yesterday with a ten 2-axle consist for about three hours while working on my rock pile. It seemed none the worse for wear and its two motors were only drawing 1.4 amps @ 19.2V on the steepest part of the line (about 0.8 amps downhill).

Phil S.
 
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You won't find any increase in wear in three hours!

A comparison of the current draw is good though, less than double indicates that the motors are most likely fine.

But this says nothing about the gear train. Keep the gears well lubed. Look at them after a year and see what is up, although gears are relatively cheap as long as they are available spares.

Greg
 
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