Category: locomotives

Locomotives of the Thunder Mesa Mining Company

 

Following last weeks video on No. 7, the Frank Thomas, I received a lot of questions about Thunder Mesa's locomotive roster. Here, then, is a complete catalog on every locomotive running or currently planned for the TMMC, with notes on construction, origin, and specific details. Special attention is given to the line's newest locomotive, No. 11, the Sam McKim; a HO to On30 conversion that was recently completed.

Thanks for watching, amigos!
Dave

Thunder Mesa Locomotive Story: No. 7 – Frank Thomas

 

Thunder Mesa Mining Company's locomotive No. 7 is an 0-4-2 Porter named in honor of Disney animator Frank Thomas. Follow along to see how I upgrade this stock On30 Bachmann engine with custom decals, paint, details, and a new "Big Thunder" style laser cut cab. Complete step-by-step how to's on decaling and custom cab assembly. Note that this video does not cover the electronics of the Bachmann Porter.
Custom decals:
https://www.cedarleafcustomdecals.com...
Micro Set/ Micro Sol:
https://www.micromark.com/Decal-Finis...

Thanks for watching, amigos!
Dave

Adventures in On18

On The Horse Thief & Never Mine Ry.

 

I've added a new engine to the roster of my On18 Horse Thief & Never Mine Ry., No. 5, the H.D. Ryman - named for one of my all time favorite Disney artists, Herb Ryman. In this week's video, I show how I scratchbuilt the engine, and get into some of the particulars of On18. Allow me to expand on things a little more below.

A Primer on On18 and Scale vs Gauge

If you are already familiar with On18, this information will not be new to you, but since it is a relatively obscure scale/gauge combination, here's a brief explainer of what it's all about for the uninitiated.

The "O" in On18 stands for O scale, which in America is understood to mean 1:48, or 1/4" = 1'. The "n" stands for narrow gauge, meaning a distance between the rails narrower than the American standard gauge of 4' 8.5". The "18" refers to a track gauge of 18". Unfortunately, the terms "scale" and "gauge" are often confused or conflated by the layman but they actually mean very different things. In the simplest terms, "scale" refers to the size of a model relative to the real thing, while "gauge" is a railroad specific term that refers to the distance between parallel rails on a track. In other words, if you say, for example, that a model is N gauge, what you are really indicating is only that it runs on 9 mm gauge track. Whereas if you say it is N scale, you are specifically stating that the model is 1:160th the size of the real thing.

The Thunder Mesa Mining Company model railroad is built in On30. Using the formula above, this translates to O scale trains running on 30" narrow gauge rails. Its wholly owned subsidiary, the Horse Thief & Never Mine Ry is built in On18. Though still the same scale, that means the equipment is somewhat smaller because it runs on a narrower gauge track.

To model On18, we often use N scale mechanisms, wheels, etc. as a starting point. Using them in O scale means we are effectively changing their size relative to the real thing. Track is a good example of this. In N scale (1:160), 9 mm gauge track represents American standard gauge, 4' 8.5". The same 9 mm gauge track used in O scale (1:48) shrinks down to become 18" industrial narrow gauge.

This is the same formula used to model On30. HO gauge track scales out to very near 30" in O scale, and so HO scale mechanisms, wheels, etc., can be repurposed for On30.

To further confuse matters, there is HOn30, used by some modelers in HO scale (1:87) to represent 2', 3', or 30" narrow gauge. Just like N scale and On18, HOn30 also uses 9 mm gauge track and components, and fortunately for the On18 modeler, many of these can be repurposed for O scale. For example, the Horse Thief & Never Mine uses Peco HOn30 track to better model On18 track. The scaled up and wider distanced ties look better than standard N scale track would.

An On18 Baby Climax

To build my On18 "Baby Climax" locomotive, I started with a smooth running and reliable Kato 11-106 N scale 4-axle mechanism. Then it was a matter of designing and building a somewhat plausible model to fit over this mechanism. I used a lot of parts from my scrapbox, particularly from old HO scale locomotives that had given their all. I never throw anything away and will sometimes buy old junkers on ebay just to use for parts in projects like this. Things like bells, whistles, and headlights translate perfectly from HO to O18 because they should look like smaller versions than one would find on the usual O scale narrow gauge equipment.  I use Micro-Trains N scale couplers with draft boxes and trim off the trip pins since these trains wouldn't have air brakes. One thing I failed to mention in the video is the extra weight added to make the model run better. During assembly, I filled the boiler with lead BBs held in place with epoxy resin.

Below are some photos from the build and of the finished model.

About the Climax Locomotive

The Climax geared locomotive was the invention of a skilled lumberjack and machinist named Charles D. Scott. He brought his drawings to the Climax Manufacturing Co. of Corry, PA, and the first locomotives of his design were built and delivered in 1888. Climax locomotives of ever improving design were manufactured until 1928 and more than 1,000 were built. Many loggers and miners considered the Climax to be superior to the similar Shay in hauling capability, stability, and performance.

My model represents one of the earliest models, known as a "Class A Climax." They had either vertical or "T" type boilers, with two vertical cylinders mounted in the center. Their construction was similar to that of a flat car or gondola, with boxy wooden sides built up to protect the crew and fuel from the elements. Most had a round water tank in the rear, though my model employs a rectangular tank to save on space. Though I've never seen a photo of a Climax locomotive this small, I'd like to think that such a critter was at least possible.


Thanks for following along, amigos. Registered users can leave questions and comments below so, please, join in the conversation!

All the best,
Dave

Thunder Mesa No. 8 ~ The R. H. Gurr

The Bob

Thunder Mesa's newest locomotive is a trusty and reliable 14-ton Stearns-Heisler, circa 1895. The repainted and detailed Bachmann model is named in honor of Disney Imagineering legend, Bob Gurr. It has always been Thunder Mesa's practice to name its locomotives in honor of Disney artists and Imagineers, and If you're not familiar with Bob Gurr, you should be. He designed just about everything with wheels in the early days of Disneyland, including the Monorail, Autopia cars, and Main Street vehicles. On the Thunder Mesa layout, the R. H. Gurr wears the number 8, and has the distinction of being the first geared locomotive used on the line. Lacking a third truck, #8 has something of a short, squished appearance, and that has earned it the nickname of "The Bob" with the Thunder Mesa crews.

Heisler History

Thunder Mesa's R.H. Gurr locomotive is based upon a small, 14-ton version of Charles L. Heisler's 1892 patented design. Heisler's design featured two cylinders canted inward at a 45º angle, with power transferred via a center mounted longitudinal drive shaft connecting enclosed gearboxes between the truck frames. Outside connecting rods then distributed power between the wheels. This was a variant similar to the Climax design where the cylinders are canted at an angle but mounted inline with the locomotive boiler.

The Stearns Manufacturing Company of Erie, Pennsylvania built Heislers from 1894 to 1907, when they reorganized as the Heisler Locomotive works and continued producing the design until 1941. As befitting a locomotive name in honor of Bob Gurr, Stearns claimed that the Heisler was the fastest of the geared locomotive designs, but with the same low-speed hauling ability as a Shay or Climax.

Though a later model, Roaring Camp & Big Trees Narrow Gauge Railroad's Stearns-Heisler #2, the Tuolumne, inspired some of the color and design choices on TMMC's #8. The Tuolumne originally belonged to the fabled West Side Lumber Company where it wore the number 3.

 

The Bachmann Stearns-Heisler

Bachmann's On30 version of the 14-ton Stearns-Heisler is an accurately detailed and fine running model without any of the split gear issues that plagued their Climax and Shay offerings. Mine has become the reliable workhorse of the TMMC and you can see it earning its keep at most Open Studio days. I look forward to adding another to the roster at some point in the future.

For this model, I replaced the original cab with a Banta Modelworks cab kit and stained the wood cherry red. Then I stripped the factory paint and decals off of the tender and repainted it with a gloss Hunter Green, painting the cab window trim to match. I replaced the headlight with a backdated box-style headlight salvaged from an old Bachmann Porter, then built up a new load for the tender from real Utah Juniper twigs, split and stacked as cordwood. The pilots and running boards were all repainted to add realism and dull the shine. Custom water-slide gold decals where printed for me by Stan Cedarleaf, and the crew is a pair of repainted Arttista figures. The tools and details are white metal castings from Wiseman Model Services.

A Trip Through Thunder Mesa Country with the R. H. Gurr

Sit back, relax, and enjoy this video tour of the layout and some insight into the building of the R.H. Gurr.

 

I hope Bob will forgive me for naming a slow, geared locomotive after him. He would probably prefer something sleek, fast, and candy-apple red!

Thanks for checking in, amigos. Adios for now!