Improving the Tractive effort of small steam locomotives

 The small locomotive curse 

I'm sure a lot of us have been here. You bought a new engine for your model railroad, you put it out on the tracks and find out that it can't pull the skin off pudding. Those grades you put on your layout don't help you either. In the realm of diesel modelers and large steam locomotives, there's a plethora of options to help improve a models tractive effort involving lead sheet, Cerrobend, and tire weights. Of course these models also have the space to accommodate these large weights.  

Those of us who use small steam locomotives don't have many options here though. Our space inside is extremely limited and the small size to begin with doesn't lend itself to providing much weight. 

There's been a few solutions throughout the year, none of which I thought were really practical for my purposes. I refuse to use things like powered rolling stock as I don't intend to do a lot of consisting when switching on the branch. Double heading is always cool, but of course they didn't always have a double header in service. 

"But is this a problem?" I hear some people in the audience say, "those little engines didn't pull that many cars in real life either". This is one of the big myths involving late 19th and early 20th century trains that always seems to get repeated. There's photos of single 4-4-0's moving 30+ car trains, a C-16 running into Gunnison with 23 cars from Sapinero. In Durango to this day the D&S operates heavy passenger consists with single locomotives, only getting into double header territory with 14+ cars, and that's with a 4% grade! On the Falcon branch itself I have photos of two of the ten wheelers at Eastonville with more than 20 cars set to head for Denver. That did involve both locomotives moving the 20+ empties up the 2.5% grade coming out of Parker. The entire thought process of "small engines didn't pull many cars" I believe came about as an excuse by modelers to justify the lack of tractive effort their models had. 

Remember that the locomotives were not rated for a certain number of cars, but rather in terms of tonnage. The C-3E's had a tractive effort of 21,380 pounds, which on the Falcon branch gave them the capacity of about 15 cars. It wouldn't be ideal to run the locomotive at tonnage all the time, but even if we set the target to 10 cars on the model, that's still far more cars than the myth purports these small engines could pull. 

Subject example: Bachmann Ten Wheeler

A bachmann ten wheeler leads a short 6 car train at a Pikemasters setup in Pueblo. This train was almost too much for the locomotive as it stood, it was a struggle for this engine to move 6 cars around the layout.

My first "victim" that I was going to make into a C&S C-3E was a bachmann 10-wheeler from the new blue box run. These models have a die cast boiler, but are somehow lighter still than the original spectrum 10-wheeler model. It's performance in the tractive effort department was, uh, not great. The first show it performed at I found it could barely do 6 cars and a caboose. This was a struggle for it to just perform that task as well, with the locomotive slipping to a stop on some of the curves. 

To say I was a bit disappointed by these results would be putting it mildly. The C-3E was one of the largest locomotives that the branch had in use and I really needed more power than what this locomotive had. I searched for one of the spectrum releases of the 10-wheeler as I knew they were a touch heavier and had decent tractive effort from what I recalled. 

The Bachmann Spectrum 10-wheeler running on Pikemasters. While a better puller, it still wasn't setting any records.

At the first Pikemasters show with the Spectrum 10-wheeler, I did some testing and found out that yes in fact, the Spectrum models do have more tractive effort than the new run models. However it wasn't a night and day difference. Essentially meaning I could now run my 6-7 car trains without wheelslip on the curves. approaching 10 cars was pushing it and this of course was on a flat modular layout, if I wanted to have the grades of the real Falcon branch I'd need to do some modifications.

The steam era guys don't get asked to run the track cleaning car often, and this is why. 3 locomotives to just barely be able to pull the sled around the layout. 

A whole different thing: brass engines

And this is about all 637 would do.......

I had also purchased a New Jersey Custom brass K-2 ten wheeler when I started modeling the Falcon branch. Not an uncommon sight on CB&Q branch lines in Colorado, they did occasionally get borrowed for branchline service on other C&S branches. I rolled with the "might have" card and bought this engine, because who doesn't like a Belpre firebox? 

Of course after all the work to paint the model and remotor it, I came to the sad conclusion that it might not be best suited for operating on the branch. 3 cars and a caboose was about all it could do on the modules, and that was pushing it as well, slipping all the way. 

This all got me thinking "what can I do to help these small engines out?"

 The game changer: Roundhouse 2-6-0

Roundhouse 2-6-0 with a long train at a Pueblo train show. 

While I was still figuring out a method for tweaking the Bachmann Ten-wheelers to be better runners, I had purchased a stand in locomotive that has been covered in other articles on this blog. A Roundhouse 2-6-0 from the newer runs. I expected the model to be a good runner in terms of smoothness, but what I didn't expect was how much tractive effort the thing had! 

With a fully die cast boiler and chassis plus some traction tires, the little 2-6-0 could easily outperform almost anything else I had. Walking away with more than 20+ cars in tow at one of the Pikemasters shows in Pueblo. It even had a neat party trick where it could "quarter slip" if it was heavily loaded, breaking traction on spot before finding grip again. 

I was really happy with this discovery and I wondered how exactly I could get this kind of performance out of the bachmann models, maybe even some of my brass. 

Solution: Weight, lots of weight, plus some snot.

I figured if I was going to match the Roundhouse performance, I'd need some similar weight in the Ten-wheelers. But where to put the weight? The inside of the bachmann ten-wheelers is already crammed full of a split frame weight. 

I found a solution in 2 things, little rolls of Lead sheet, and Tungsten putty. 

https://a.co/d/jlEZVLs  Tungsten putty at Amazon

https://a.co/d/2Jzcf0g    Lead sheet rolls at Amazon

The lead sheet I cut into pieces that are glued to the underside of the running boards and into larger flat areas, like the cab roof and cab floor. 

The tungsten putty I used on the bottom of the locomotive, filling up every nook and cranny I could find that wouldn't be visible to a viewer. 

Underside view of 312 with the tungsten putty and lead sheet installed. note the added bullfrog snot on rear drivers. 

Side view of 312, nothing visible from this angle. 

The addition of this weight helped out 312 IMMENSELY, with the tractive effort almost doubling. Some experimenting found that moving the weight so the fore and aft center of gravity was over the center driver made much more of a difference than even more weight that wasn't centered. 

312 now could pull much more, but it was also still very slippery, liking to slip at certain points in the track while under a heavy load. This brings us to the final step I performed on the locomotive, Bullfrog snot. 

https://a.co/d/htQQPw2 :Bullfrog snot from Amazon.

Bullfrog Snot is a liquid traction tire (liquid latex I believe?) that you can add to the wheels of locomotives to improve their tractive effort. I remember this stuff was relatively new when I worked at the hobby shop during college, but it works wonders! A little pricey but a single jar will last you forever. 

This stuff is a little tricky to apply and get a nice smooth, even coat. It takes some practice, but it also can be removed easily with a hobby knife if you desire to redo it. 

So now that 312 has the traction tires and the weight, how does it perform?

The Verdict:

After the installation of the weight and bullfrog snot, I took 312 out at one of the TECO shows. I was blown away, 26 cars and a caboose without batting an eye. I started working on implementing the same scheme to my other steam engines in need of aid. 

First up being the brass K-2 ten wheeler. Remember that it could only do about 3 cars before and that was a struggle. 

Now 637 could pull 12+ cars around the layout without issue! 

I'd done it, I'd cracked the solution for improving the tractive effort of small steam engines! 

Give this a try for your small steam, it really does help turn some of the anemic pullers into real powerhouses. 

A Falcon branch combine

C-3E #312 with the combine just south of Denver

One can't look at many photos of my modeled era on the Falcon branch without seeing a combine on the end of the train. The combine assigned to the service appears to be pretty consistent through all the photos. Occasionally a 2 car consist substitutes for it with a separate baggage car and coach, but this seems to become less common through time. However I've never been able to nail down for certainty what car number this combine was.  

A note in the Jim Jones book "D&NO, in the shadow of the rockies" mentions the Falcon branch combine was retired and became the yard office in South Denver. In the "Colorado Road" book, there is a roster at the back of the book of every known disposition of passenger equipment from the C&S. I see that Mail-Coach #327 is the listed as "dismantled 6/44, body to South Denver yard office", so I believe this to be combine mentioned in the book. However the Colorado Road book also mentions that this car was converted to an Outfit Diner in 1923, a full decade before the Doodlebug started running passenger service on the branch. 

In fact, the only form of combine I see that lasted long enough to make it to the end of the Falcon branch was Baggage-Coach #278, which lasted until 12/1940 in that guise. This car was a Pullman built car of correct dimensions from what I see in the photos, it started life as a UPD&G mail car which also lines up with its use on the branch. 

Photos of the grounded car in South Denver don't particularly help identifying which car this was, as the windows have been traded out for building type windows that don't match anything on any combine the C&S had. 

The particular combine used on the Falcon branch also has a unique quirk that makes it stand out in pictures. It has a blunt front end and an actual platform on the rear. Finding models that matched this proved tricky as you'll see in a moment. 

If you have any additional information about the Falcon branch combine, I'd love to hear more about it.

The Model

I plan to have a total of 2 models of the combine. "Why?" I hear you ask. This was a decision I made to help accelerate getting some more accurate trains operating and for photos. I purchased a LaBelle kit to be my combine but knew it would be some time before I got around to actually building it. Later at one of the TECO shows in Colorado Springs, I found another pre-assembled LaBelle combine, this one was not an exact match for the Falcon combine, but it DID have the blunt front end, and an enclosed vestibule on the other end. 

My thought process for this combine was to cut off the vestibuled end of the car and make it just an end platform, while leaving the blunt end alone. This would get me the look I was looking for, even if the windows don't quite match the individual ones on the prototype. Someday I might modify this car to have individual windows, or maybe I'll just build the other kit I purchased at some point and just switch to using that all together. 

The car sat around for a few years before I bought a pair of Central Valley trucks for it at yet another TECO. With a TCA show fast approaching (Spring 2025), I worked on getting the car up to speed for the show. I replaced some missing glass material from the inside of the car and also installed a pair of Tomar marker lights on the rear of the car. For the time being these are battery powered, but someday I'll equip the car for track pickup with a capacitor. 

I hacked off the entire end wall of the car and proceeded to fabricate a new end beam for the car. It's still a touch oversized but I'll get a better file to it here at some point. Some railing from a MDC parts car completed the end look of the car. 

The combine sitting on the bench after the modifications. 

Now with lights!

The Combine running on the tail end of my train at the TCA show, April 2025. The brakeman on the rear deck is actually a 3d print of myself, I got scanned for the print at TCA a few years ago.

At some point I'll get around to getting some people inside of this car along with some interior lights as well. This combine will serve me well until I get around to building the more accurate combine from the LaBelle kit.