Large Scale Central

RC&G locomotive #16...the "Mastapod"

Some projects take on a life of their own and this was one of those. My initial goal was to convert one of my ‘Annies’ that had donated its drivers to another project and create a heavy consolidation that better fit the needs of my pike. To do this the ideal size of the drivers needed to 1 3/4" diameter. However I found this size to difficult to find, probably why Barry, when he made his consolidation conversion, ended up casting his own drivers.

I did have lots of Aristo C-16 drivers and they were small enough that I could fit five axles worth under the ‘Annie’ and while I thought at the time a narrow gauge decapod would be an anomoly in the US they were quite popular in other countries in meter gauge. While discussing this on the chat one night Bob Cope found this photo of a 3’ gauge decapod that Baldwin had built for a Mexican railway.

So my idea wasn’t all that far out. I had no plans to copy the Baldwin loco, my plan had been from the start to use as many of the ‘Annie’ stock parts as possible to keep the project from becoming the multi year project that most of my other locomotive building projects have become.

To see how this would look I built a mock up with a wooden frame and plastic side rods. I liked it, it had a hunkered down look that said “narrow gauge” to me.

Once that was done I milled up the frame in brass. The drive uses two Aristo modular gear boxes to power the flanged drivers at each end. The line shaft connecting the two was driven using a cogged belt and pulleys that reduced the motor speed in half, that combined with the roughly 21:1 reduction on the gear boxes gives an overall ratio of around 40:1 which gives a reasonable top speed and will help the anemic Bachmann motor provide power. The center drivers were sprung and given roughly 1/8" of travel to keep them in contact with the rail.

The ‘Annie’ frame required a good deal of butchering to make the new drive fit but in the end enough plastic survived to provide some structural integrety. I then did some modifications to the boiler and super structure. Since they are fairly visible through the cab window I added some accurate injectors and associated plumbing. I also felt the larger engine need an extra air compressor, this was added and then properly plumbed.

I shortened the pilot converted it to foot board style and added a working coupler.
I never really liked the stock ‘Annie’ tender, it’s a standard gauge tender on narrow gauge trucks (as was the prototype) and looks too wide to me so I created a lengthed tender by stretching a C-16 tender. This made installing power and sound much easier as the original C-16 tender was rather cramped. Painted up and with some extra details it looks quite the part to me.

I wanted this to be my primary heavy hauler until such time as I finish my model of EBT’s #14 so I wanted it to have some heft. I made a mold and cast a lead weight that weighed just short of 6 pounds. Time will tell how long the Bachmann motor will last but while it does it should have little trouble handling my 4% grades with a heavy train.

Once everything was together I realized that since the drivers were set far back on the frame (required to be able to use the ‘Annie’ Main rods and valve gear) that I had a big open area behind the cylinders. So I thought ‘what the heck’ I’ll make a four wheel pilot truck making the locomotive a 4-10-0, back to fantasy land again but what the hey. There was at least one narrow gauge 4-8-0 built and used by the C&NW narrow gauge.

Who is to say a 4-10-0 could have been built too. So to me a cross between a Mastadon and a Decapod would be a Mastapod, or I suppose it could be a Decadon or maybe some other dinosaur.
Anyway here is the final product. These are builders photos and it will get dirtied up a bit before going into service. I suspect when spring comes and it gets to run on the layout other issues will rear their ugly heads but for now I’m happy with it.


Great build.
I have two Annies gathering dust, You inspired me to do something with them. Not a Decapod, but some kind of backwoods logging theme.

Wow, your build is amazing! You must have very wide curves on your RR. The flanged drivewheels on your build are so far apart I know that loco wouldn’t like my RR.
Any chance of a video of it in action?

Thats awesome, as the Mandalorian would say “This is the way”. If you want something, your going to have to build it.

That is an impressive beast. I love it.

Very nice Gary. I love your use of the Aristo gear boxes with the Annie motor.

One thing I noticed before you run it around the layout, is how close to the ties the valve gear comes. On my indoor it would clobber the hinges on my bridges :open_mouth: Could just be the camera angle though.

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Great modeling, Gary…well done, young fellow; VERY well done. Thank you for sharing…

Ever seen a B&O Mud Digger? They worked fine! But I agree with the sentiment. Dropping the body and cylinders using smaller wheels makes the combination lever from the valve rod to the bottom of the crosshead longer than desirable.

What amazing craftsmanship Gary, she’s gorgeous!

How does the 8:71 blower incorporate into the coal fired scheme? Water injection does help though. Glad to see this posted as it should be!

Tank you !

That’s a beautiful job Gary, anxious to see how it tracks.

Here is a link to one I have always wanted to build but have never had the gumption to start. Besides I don’t think it would ever handle any realistic garden curves.

If I may suggest a dinosaur, perhaps “Awesomenosuarus?” This big guy is outrageously cool!

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Videos will need to wait till the line is opened, probably late April early May, winter has been harsher than it has been for several years so it remains to see what needs to be fixed

It does sit low but the bottom of the valve gear sits even with the top of the rail and I think the only place that might be an issue is grade crossings. It looks to be an easy job to shorten it if need be. I’m anticipating clearance issues in other areas though. As for the Bachmann motor, I had given away all the Aristo motors I had…Blessed are the gifters as they will become motorless !

Very impressive work Gary. Something few would ever attempt.

What Doc said!

From that angle the gear looks OK.

Thank you, I’m also interested to see how well it tracks :thinking: I also appreciate the info on the CP’s loco, at least I know now it isn’t total fantasy, I guess the old saying " there’s a prototype for everything" applies. The Gobernador name is almost as bad as Mastapod !

Thanks to all who posted, I’m glad it was so well received ~

Isn’t that what they call Arnold when he was in office, although I think they changed the d to a t to link to his movies.

From Wikipedia…
The Governator was a planned superhero franchise for children developed and produced by Stan Lee and co-developed with Arnold Schwarzenegger.