Improving Our Steam Engines Performance


trailrider said:
I do recall (vaguely...don't ask me where, but I did see it) that at least one railroad had a booster in the lead tender truck.
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Indiana Harbor Belt used them on some USRA 0-8-0s. I don't know much more about it than that, other than they were maintenance nightmares.
 
trailrider said:
Interesting that your #144 would work on DC. Must have a dual-mode decoder inside.
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I don't believe that any of these early Atlas S2 had decoders in them in stock form?

I also found a second S2 in my inventory, and it worked as well as a pusher on those steam engines I ran experiments with. Surprisingly it appeared to be geared such that it rather closely matched those steamers.

To the contrary that Proto C-Liner chassis did not appear to be quite as 'cooperative' as a pusher in the pure DC mode.
 
Proto 1000 F3 chassis?

Perhaps these older chassis might make a good pusher? They have a shorter wheelbase than the C-liners which could be put under an older style express boxcar??
 
And yesterday I experimented with a Broadway F7 (blueline model). It also had plenty of weight and power, ...but with that sound decoder in it it did not consist with the pure DC steamers as well.
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Pusher Tender

...from another forum
Because I model in N scale this trick has been used often to improve power pulling

With all the mechanisms on hand and diesel frame compatibility with steam tender this seems an easy way to go.

Not so easy unfortunately because of some factors

First you need a perfect stock running locomotives which run flawlessly with a good mechanism, second the synchronization of the speed and gear ratio need DCC to be achieved correctly between the locomotives itself and the powered tender, this is important especially when passing through turnouts where the tender of the locomotives must no be a pusher or à puller.

Good achievement were done with only a powered tender pushing the locomotives, a concept used by Fleischmann in most of his N scale locomotives with powered tender only; this ended with powerful and fine running locomotives

The boiler of these locomotives is full of weight and the running wheels roll without any gears, the locomotives is a full dummy unit. These N scale locomotives like a German BR 44 are far most powerful in N scale than a Bachmann Spectrum 2-6-6-2 or any other US mallet models in N scale

When seeing the power of a diesel in N scale or in HO this solution need to be investigated more deeply by using a diesel tender pushing a dummy steam locomotives , a quiet easy heavy repowered solution, even with a second water tender with a same diesel frame.

In N scale most of the time steam locomotives are repowered or receive new mechanisms and weight is largely added; shift with Kato or Micro Ace steam frame is also often done.

Dual motoring has not proved to be the easy way and need minitious tuning to run fine; if power is needed it first need to run perfectly which is difficult to achieve with dual power.

Anyway one of my project is to modify a Rivarossi-Atlas N scale Y B 6 with two motorized Kato mechanisms of a small 0-8-0 Japanese steam locomotives which includes 5 poles motor and flywheel already done by several members of N Track, I share the slowly ongoing project for a 0-8-0 Indiana Harbor Belt heavy switcher using such mechanisms
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Marc
I speak about it in my previous post.

This is not often used and most of the time not considered.
But Fleischman has used the trick both in HO and in N scale with their steam model locomotives.

The result are excellent to no say perfect and respectable.
The tender of these locomotives is a powered ones, with four ( most of the time) or six wheel bogies.
The inside of these tender is like a diesel model frame with electrical power on each wheel and motor power on each wheel surrounded by an heavy weight.

The steam locomotives is a real dummy; wheels are not motorized and run free pushed or pulled by the tender .there is no gear on the axles, it's a free rolling locomotives.

The boiler is full of weight and contains decoders speakers and all the technical options for the locomotives, all boiler wheels pick up electricity.


All these models are extremely powerful, some of the tender wheels have sometimes traction tires, they often show power of over 20 streamlined passenger cars on level track or long freight train even on non level track.

The same result is obtained on N scale models by Fleischman

In any case these models are smaller steam locomotives besides US counterparts but are far more bigger puller than any U S models in HO or in N scale, just with a powered tender and a dummy locomotives.

The approach is poorly investigated but used by some fellow modeler with excellent results .

In the N scale community this trick was often used in tiny steam locomotives which left plenty of space to put decoder and a big geared motor in the tender.

And if you want to have a monster of pulling, a powered water tender could be added.

Not often used it seems a quiet easy way to obtain a good puller with a steam locomotives.
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Tender Driver Pushers
Actually that Fleischmann looks like an interesting approach.


Tender driven pushers with unpowered boiler might make things a lot less complicated to engineer and build,...and likely far less expensive to manufacture? Plus good big space for speakers up in the actual locomotive,.... (where the sound should be coming from)
 

my Roco Steamer​


my Roco Steamer
This is Roco 2-10-0 steamer I spoke of. I believe it is an early BR44 model by Roco
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When I first viewed this loco I thought perhaps it had just a very heavy small tender with a can motor that pushed the boiler unit. On closer inspection I found a drive shaft extending out the front of a flywheel that was mounted on that motor in the tender. This drive shaft went to some sort of gearbox in the boiler that provided rotation of the drivers of the boiler unit.

I could not determine the details of that gearbox, nor its robustness without further disassembly of the loco, which I did not want to do at this time. It appeared as though this gear box operated on the rearmost driver axle. The questions that remain in my mind are, 1) was this a real positive effort to provide driving power to those drive wheels, or 2) was it just an effort to provide rotation motion to the drivers??

That can motor in the tender also drove the 4 axles of the tender
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Not sure of the exact details of this tender drive either, without further disassembly. I would rather like to find specific drawings/photos rather the taking my model apart at this time.

Some notable features of this Roco steamer:
1) There is a very unique and adjustable drawbar connection between the boiler and the tender. It allowed that very close spacing between the two, and it could adjust its length when negotiating tighter turns (supposedly as little as 18”)
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Here are a few photos of the engine on some 22” track I had,..
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There are 2 flexible panels on either side of the loco's cab area that hide that driveshaft between the two.
It took me a while to figure out how that special drawbar worked.

2) The axles on both the boiler and the tender are allowed to move side-to side by a considerable amount. This is one of the reasons she can run on small radius curves.
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Here are the ones on the tender. Note that the side-to-side allowance is considerable, and that allows this tender to NOT have to use rotating trucks for even small r curves.
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3) Here is another very similar model of theirs that makes use of traction tires on 4 of 8 of those tender wheels,...BR43?
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I believe it might have been indicated that this loco didn't find a need to provide that drive shaft to the boiler drivers? (don't quote me on this yet, I need more time to research,...but the traction tires back there would seem to indicate this possibility)

EDITED: That BR 43 loco is the one I just purchased a couple of nights ago. I will disect it when it comes in, and get it a test run to compare with my other Roco steamer.
 
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A German WWII Kreigslokomotive (War Machine) Haven't seen one of those in a while. I believe the idea was to give you a type of "all wheel drive." also you will have noticed its hard to get wheel slip as all the wheels are synchronised with the tender via the tender drive shaft, plus with traction tyres fitted, nearly impossible I would imagine. It's a drive system that is hard to find now, you can still get the drive train but not in any manufactured loco's I know about, as it not one that has a lot of demand it's more of a niche market, usually for kit builders and only then for specific builds for your layout (you have lots of steep gradients or intend to haul a lot of weight etc,) and technology has moved forward with better engineering, motors, use of flywheel's etc.
Tender driven Loco's are now old by modern day standards but still going strong, I have 6 of them and all run well, but do have a tendency to derail the loco if you've used a bit more throttle on a tight curve, unless you've added extra weight to it, and if your using a prototypical short coupling you can get buffer lock, which I see your Roco cleverly avoids.
Our tolerance's these days towards our models seems now to be one of exact replication, it has to look, drive, even weigh as prototypical as possible. The slop you observe on your axles is for exactly the reasons you say, otherwise you would only be able to run the loco on certain larger radii curves, (most new models in the U.K actually tell you the minimum curve it will run on) but by todays standards most would find it unacceptable to have that degree of axle slop.
 
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The typical British and European, and most certainly Asian, layout has tighter curves than many (I don't think it would be wise to say 'most') N. American layouts. This is due to space in most EU/Asian homes. As a result, the rolling stock is designed to reflect the typical layout's constraints. But, they also reflect the scale reality in those places where properties were already densely populated and situated when the earliest railways were engineered and created. As Model Railroader mentioned in the first early review of a Trix Big Boy 4-8-8-4 about 16 years ago or so, the drivers are quite a bit smaller in diameter than would have been acceptable to a N. American modeler interested in a closer approximation, and the axles all have more side-play so that they can operate on typical EU and N. American layouts with 18" curve radii.

Meanwhile, the hobby in N. America has begun it's creeping inflation away from 18" being the de facto standard curve in the HO hobby, as an example. With the advent of ultra-realism in the magazines, and on the forums where people post their photos of their layouts, and with purchasers wanting more and more realism, there is pressure to make locomotives that come closer to the prototype in both appearance and to a lesser extent in operation. This means, and it comes often from suggestions and encouragement here and on other forums, to widen one's curves to the extent possible. I often do this myself, not to encourage the hobby to keep expanding its 'girth', but so that people spending money and time, and maybe treading on their partners' good will (you know what I mean), will appreciate that each of us expands their 'druthers' and we find larger locomotives to be appealing. If you're stuck at 18" curves, you won't be happy with Walthers' heavyweight passenger cars that are a scale 85' long AND have diaphragms hung over near-prototypical couplers. I try to encourage people to be honest, and farsighted, and to anticipate that they will find themselves constrained and wanting to undo their expensive layouts. Yeah, maybe not, but.....maybe....too.
 
You have to renew the traction tires of your BR44 (erroneously by Roco as BR43 labeled). Without the tender has it's difficulties to push the loco, even with no train behind it. Because the force path is going over the rails you have to subtract (-) the rolling resistance. And there is a lot of axles, rods, valve gear etc. of the unpowered loco to be subtracted from the traction force of the tender.
Lutz
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My particular Roco engine today pulled 14 cars up my 4.5% grade by ITSELF,...with no traction tires. I was impressed.

It likely might have done 15 or 16 as it never stalled during those multiple runs, and a few of the cars I happen to have hooked up at this time are not metal wheels, nor totally frictionless tuning yet.

I was so impressed I bought another very similar Roco off ebay just tonight. (my Christmas present to myself)

EDITED: I have since discovered that this original Roco engine I have, also has 4 traction tires on its tender. They fit so firmly and looked like slight dirty metal wheels, so I did not discover the truth until I began to reinspect them ever so closely.
 
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And because tender drives does'nt work without traction tires, today still traction tires are mounted on pusher tender wheels by the factory.
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Then can you explain my recent experience,...14 cars up 4.5% grade,...NO traction tires on either unit.



In former times traction tires lasted some years; but for to date new purchased traction tires, they have improved the obsolescence of the material for them. So you have to renew them all after about 6 months.
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Isn't the replacement of traction tires on the tender wheels a LOT more simple than on the DRIVERS that have all the connections rods attached?


And did you know? Roco has mounted traction tires on loco drivers even when this loco in non powered and is pushed by the tender. Wonder why?
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I suspect this is to prevent some of the 'sliding action' of the main drivers that might show up without the mild friction improvement provided by at least one axle's equipped with a traction tires?


I will experience these tender traction tires first hand with my new purchase that has traction tires on 2 of the 4 four tender axles.
 
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The pure weight of the Loco in itself would be sufficient, you could probably get 16-18 without traction tyres

But I really want to know now, what your loco will pull up the gradient, with and without traction tyres, I don't think there would be a huge difference between the two.
 
Perhaps we will find out more when that new purchase arrives, ......very similar size loco and tender. It has some traction tires on its tender.

I would have liked to seen how that existing loco would perform WITHOUT the drive shaft powering those boiler drivers,...in other word JUST a powered tender doing the work?? I'm not sure but that new purchase just may be set up this way,..no connecting shaft between the tender and the boiler??
 
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The Loco can be disconnected from the shaft, I think it simply slides out. I vaguely remember my dad removing it and making a new one, because I broke the shaft when I dropped it. (in my defence, I was 6).

Keep us informed about this, I'm getting intrigued as to what your comparison results will be.
 
That loco arrived this afternoon, and boy is it a heavy little dude. I was real excited, particularly when I rotated the driver wheels freely, to realize that those drivers are NOT powered. It is solely the responsibility of the tender to drive this engine.

But then I took a look at the traction tires on that tender and noted that one was totally missing, and the other 3 had gaps in them. I wondered if perhaps they still had enough 'body' to at least run the loco by itself? That was not to be, they simply feel to pieces in the first few feet of running.

It appears I am going to have to go out searching for some traction tires for this little beast, before I get to run any test !!

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I discovered a problem with that new Roco locomotive. I decided to just clean up all of the 8 wheels of that tender and give it a try without it's traction tires.

It experienced sporadic electrical pick-up !! Don't know why it did not dawn on me that OF COURSE those traction wheels do not have electrical pick-ups. That means only 2 axles of the entire locomotive pick up electrical signals from our tracks !

I can only think of 2 solutions to this problem:
1) add some electrical pick-up wheels on the boiler unit and run a couple of wires back to the tender.
2) switch out those traction wheels on the tender to std ones that can support electrical pick-up,..or maybe at least one of those traction wheel axles, ....leaving just one set??
 
Depends on how much adhesion you're getting from the Loco and how much you intend to pull with it as to whether you swop out the traction axels, personally (as you seem to want a lot of pulling power) keep the traction tyres, and add wipers to the front two loco axels, receiving power from different sections of the track is always a good plan and you get the best of both worlds, electrical continuity and pulling power.
 
Yes I was trying to see if those driver axles/wheels under the boiler section were isolated from one another across the axle,...so I could add pick-ups there. Somehow my meter gave me conflicting answers?...may be the operator...ha..ha.

I would assume the spoke areas of those driver wheels are plastic??
 
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