Improving Our Steam Engines Performance

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beiland

Well-Known Member
I'll admit right up front, I am a hopeless steam engine fan. And the last 10-20 years has seen some really marvelously detailed plastic steamers that often rival the brass ones. And those plastic ones run better (smoother, better electrical pick-up, etc, etc) than many of the brass ones.


But there is one big failure that still persist. Their pulling power just does NOT match that of those new diesels. We keep adding as much weight as possible, and work on the electrical pick-ups,and add troublesome traction tires, etc,... but we still can't match those diesel model trains.


Today I was prepping a few of my trains to run on Thanksgiving holidays,...both steam and diesel engines. Combining the two types in one consist has me wondering how we might expand on this idea??
 

beiland

Well-Known Member
Yesterday I spent some time assuring that I had ALL WHEEL pick-up on my Bachmann 4-8-4, and that it was well lubricated, and the wheels were all clean. It was running very good, BUT it still could not pull that many cars up the considerable grades on my stone viaduct. I even added some external lead weights to the body of this steamer,..that helped, but I knew I could likely never get enough weight into that engine to make a really big difference.


Today I thought what if I added one of my Proto 2K engines into the consist. Its a 1K model of the DL109,..lots of weight, lots of pulling power. I put it behind the steamer. (BTW the B-unit there is unpowered)


image%28321%29.png






With both the steam and the diesel pulling it seemed like I could just keep adding cars, and it would pull them. I began to think of how I might disguise that diesel engine into some sort of 'powered freight car' to make it appear as though the steam engine was doing all the work . OR, how about adding power to the tender as a pusher?


I figured there must be some discussions of that on the forums, so I did a quick search.
 

beiland

Well-Known Member
Tender Drive for Steam

This was the very last posting added to this conversation,
https://model-railroad-hobbyist.com/node/7740?page=2


DK, a while back and for me that likely means in the last 20 years or so a gentleman was wanting to pull long coal trains with his y6b locomotives and was very unsatisfied with the pulling power. He was in n scale. His solution was to use SD diesels inside a tender body that he had made as well as a copy of a cistern so that he had his 2-8-8-2 and 2 SD units in each consist. After the initial test he was quite pleased and built several of these models. He had done this in n scale and other than the tenders being a bit longer than the protoype they were very realistic. At the time had he not made mention of this I do not think I would have noticed the additional length.
If in HO scale there are lots of really good choices for drives both in 4 wheel or 6 wheel versions and with several different lengths of frame. The one thing he did was change the side frames on the diesel for the ones on the tender. Weights can be eliminated from inside the diesel shell and others used since the tender will be much wider than the diesel body. In his case he found that all units ran very well together and would pull anything he connected to them.
If I was facing a problem like the one you mentioned I would try to keep the steamer powered and add a tender drive. Having too much power is not a bad thing and will reduce the load on both units. I do not know why manufacturers do not do this initially as we have some models with very big claims for pulling power and they could then eliminate traction tires. Also it would seem to me the addition of idler gears and gears on all driver axles blind or otherwise would eliminate a great deal of binding on drive rods of steam locomotives and make it easier to have realistic looking rod and valve gear action.
Rob in Texas


Most of the previous postings had dealt with adding power to the tender in lieu of having a power source in the main boiler. I'm wondering about having power in BOTH the main body and the tender. And making that tender HEAVY like the diesel example above so it could substitute for it??
 

trailrider

Well-Known Member
It is said that a diesel locomotive can start a train that a steamer cannot, but once rolling, the steamer can pull a train at a speed that a diesel locomotive can't. You can google a discussion of this. One factor is the diameter of the driving wheels. Another is the transfer of power from the motive power to the wheels. I don't know if the fact that the power transfer on our model "steam" locomotives is the same as our "diesels", but it may have something to do with it. One thing to note is that some prototype steam locomotives had booster units either in their trailing trucks or in a truck in the tender. These were used to give more tractive force for starting a heavy train which was then cut out when the train got rolling. As far as adding the diesels or even a steam "pusher" on a steep grade, that is exactly what the prototype did.
 

beiland

Well-Known Member
I have not done any intensive look at what might be done to any individual steam engine I have. I just know that I have a number of large steam engines, and its my understanding from lots of previous discussions, across more than a few forums, that in general this is a real problem. For instance I have a number of those VERY NICE Proto Heritage steamers that I understand have these same pulling/traction problems.


Over here I was doing some cursory running of a couple of my Allegheny and Mountain locos. You will see some photos of my grades (close to 4%), and you will see where I taped some 'wheel balance weights' onto the tops of the boilers,..
https://model-railroad-hobbyist.com/node/43723
I did that same thing to the 4-8-4 the other day, and it only marginally improved things. And that Bachmann 4-8-4 does not have traction tires. Nor do a number of my other steamers. Then you run into the problem of finding drivers for your engines that will match the engine and accept traction tires.


Those are a few of the problems I would be interested in circumventing by finding a 'disguised pusher'. Wonder if it could be generic enough to have application in our individual tenders as well as a 'generic tender/freight car',....perhaps an aux water tender for those various steamers??
 

beiland

Well-Known Member

beiland

Well-Known Member
not very much torque on that small bogie, too small of a motor in there
I was looking more at the concept. I imagine the motor size could be increased. And how about dual motors at either end of this disguised pusher car.

Didn't I see a belt drive version of this sort of truck design??
 

bnsf971

Gomez Addams
Staff member
Brian, you've discovered one of the two main reasons steam was replaced by diesel in the real world. A steam engine can only pull so much, and if you want more cars on that train, you'll need to add another steam engine (with crew). If you have diesels, you just keep adding engines (within reason) until they can pull the train. With one crew.

I remember a Model Railroader article from years ago, detailing how to convert a baggage car or boxcar into a helper engine. Don't ask how many years ago that's been, but it's been at least a decade.
 
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Patrick

Alien Attitude.
Interesting discussion.

UP had a helper steam locomotive to get coal trains through the mountains. The reason for the Big Boys was to reduce the need for multiple crews.
 

Bigboy57

Active Member
I have mostly steam engines also and in 3 different places on my layout, grades are about 3 percent.
I think steams will have a tendency to lose traction more because of the drive arms being at distance further away from the center of the wheel. This causes a slight surging of the drive wheels and the wheels break traction earlier. The wheel spin actually looks very prototypical when starting on a steep upgrade. Also, steam engines tend to be longer and unless the transition to grade of your layout is quite long, the weight distribution will be less balanced in those locations. Articulated locomotives are designed for left and right turns but they don’t articulate much vertically. I cannot pull as many cars with my big boy as I can with the challenger or shorter locomotives.
 

beiland

Well-Known Member
My viaduct grade issues are a result of my desire to permit double stack container cars to get into the central peninsula zone, requiring them to get under this bridge and this arch structures.
1637242684901.jpeg


Both of those required heights were fortunately near each other, over in that corner where the tracks were going thru the back wall into the helix area. So I needed to get to that height using one ramp on the length of the layout, ....and the other one across the width of the layout, ...15 x 11 shed interior.

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My original thoughts were how can this be that bad?,...after all there are numerous old small layout that had a figure 8 arrangement with a bridging crossover. Of course these small layouts were not anticipating running longer trains.


I'm pretty happy with my track plan, so now I just need to explore different options on making my trains negotiate it,...and I quite a few steam engines I would like to make usable,...and some of them without being dbl-headed.


I love those Heritage articulated steamers by Proto, but I would really like to see them able to pull at least 20 cars by themselves. I believe there are quite a number of other modelers that would like to see the same,...without having to resort to all the weight adding, etc to get there. What if they could simply buy a 'disguised pusher' that could be utilized along with any number of my other steamers??

Might be an interesting project for one of those manufacturers to pursue,..in lieu of those constant repetition of existing models??
 
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trailrider

Well-Known Member
I was looking more at the concept. I imagine the motor size could be increased. And how about dual motors at either end of this disguised pusher car.

Didn't I see a belt drive version of this sort of truck design??
There are IMHO several factors to be considered with this concept. To go back to the prototype, 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. (This was NOT the Erie Triplex articulated. That concept proved impracticable due to the change in weight on the drivers from the consumption of coal and water from the tender). The tender truck booster, as was the trailing truck booster under the locomotive was to increase the tractive force on starting the train. After reaching a certain low speed, the boosters were cut out.
Let us consider, however, if you did build a booster car. Would the booster be able to travel at the same speed as the locomotive? If you run on DC, you would have to figure some way to get the pusher and the locomotive to move at the same speed. With the difference in wheel diameters, this could take some figuring. If you run DCC, the helper car and the locomotive could probably be "consisted", which, of course, would requirea decoders in both, and some playing with the CV's. If you don't want to double-head your steamers, and you have DCC, would you consider cutting in a GP-7 road switcher?

Let me add that this is your layout, and the comments to follow are NOT meant as a criticism, only as an observation from a historical and engineering standpoint. I understand your wanting to have clearance for double stack containers to pass under the bridge and through the tunnel. I don't recall when double-stacks came in (my layout is in the 1940'-1960, and IIRC Trailer on Flat Car (TOFC) was in use. The other thing is that I don't believe any Class I railroads had 4% ruling grades. Union Pacific's Sherman Hill was just under 2%, and that required helper engines on most Westbound freights, at least until the Challengers came onboard. I have a 2% ruling grade with 20" radius curves at each end. I haven't really tried to see how many cars my M-4 2-10-4 can pull as the size of my layout makes more than an 8-car coal train plus waycar (caboose) look ridiculous. The locomotive, a kitbash from Mantua Mikados, with can motor and DCC, has a pull of 2.8 oz on level track, which is about 43 free-rolling boxcars on level track, according to Model Railroader's calculations.

Just some thoughts. I wish you the best of luck!
 

beiland

Well-Known Member

Rubber Band Drives


Old applications,..perhaps needing the injection of newer technologies?
Look at how many cars this rubber band engine is pulling,... (BTW the video is speeded up)


I always heard that one of the real drawbacks of the rubber band drives were their excess speed. But I wonder what newer motor control technologies, etc could do to make things more reliable??
A couple of more videos:


I was expecting this one to be even faster due to the smaller dia wheel axles, but it almost looks reasonable?


Sure looks like it could be some cheap experimenting !
 

beiland

Well-Known Member

Pusher/Helper​

Back to the pusher/helper idea.

I had been using that DL109 behind the steamers, and very successfully. What smaller engine could I be using?
I happen to have a pretty heavy little switcher engine in my inventory,...an Alco S2 by Atlas,...but could this really substitute for the DL109.

WOW, it did a great job. First I put it behind that Bachmann Northern,..
image%28325%29.png


Then behind one of my Mehano mountains,..just plain DC
image%28326%29.png

I was really pleasantly surprised. This little Alco diesel model did a great job. I was pulling 20 car trains up the more difficult ramp side of my viaduct,....4.5% grade. It turns out to have a diecast frame that gives it superb weight.

I went onward to try this little diesel by itself. It couldn't quite make it, but it came close.

I then decided to get one of my Bachmann mountains out for a try. A slight problem arose here due to the Bachmann having a DCC decoder installed, so matching the speeds with the pure DC S2 needed a bit more attention. But it also worked extremely well. (BTW I tried the Bachmann mountain by itself, and was pleasantly surprised at its performance. Double heading these Bachmann mountains will definitely be on my list).

I'm convinced that a likely solution for pushing a lot of my steam engines is disguise one of these Atlas switchers into a aux water tender. Sure would save LOTS of custom efforts at adding extra weights to that variety of steamers.
 

beiland

Well-Known Member

Atlas Loco inside an Aux Water Tender​

I was so impressed with that little Atlas switcher as a pusher, and i was thinking of that water tender disguise. I got the 2 out this morning to get an idea of the size of the two.

This looks really promising,...
image-20211125090307-1.jpeg


image-20211125090338-2.jpeg


image-20211125090409-3.jpeg
 

beiland

Well-Known Member

other Pusher/Helpers​

I went by my cargo trailer yesterday .....

I wanted to have a look at what other locos I had in there that might be candidates as pusher/helpers. I was pleasantly surprised in what I found;
1) another Atlas S2
2) an unbuilt Kato NW2
3) a C-liner B-unit by Proto 1K
That C-liner has great weight, and easy access inside the surrounding metal frame. Looks very interesting??
image%28329%29.png


I'm really getting sold on this idea of a disguised pusher/helper rather than the involved procedures to improve the traction qualities of these nicely detailed steam locomotives.
 

trailrider

Well-Known Member
Of course, it is your railroad and you can do it any way you like. But the real railroads often used helper/pushers of various types. UP's Sherman Hill westbound out of Cheyenne is about 1.3% or maybe a little more, and until the Challenger 4-6-6-4 and Big Boy 4-8-8-4's came along, they needed helpers to get over the grade with any size train at all. Interesting that your #144 would work on DC. Must have a dual-mode decoder inside.
 

Bigboy57

Active Member
The big boy was not a very good climber and the Rivarossi version which I have is the same. My Challenger ( also Rivarossi) will pull my 3.5 percent grade with 7 full size passenger cars without problems but the big boy spins out. I use the bb for freight only which is pretty much for what it was used.
 




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