Custom Projects and Kitbashes
The Ballad of The N Scale General Electric 25 Tonner (Or: How I Learned to Build a Critter) –
This is a slightly convoluted story. A member of Trainboard.com (and others) going by the handle “Randgust” has put a lot of time into perfecting N scale critters. He has built quite a few and runs a side-operation selling kits for various otherwise unavailable N scale locomotives (http://www.randgust.com/). At any rate, I found his various threads covering the trials and tribulations of building an N scale 25 Tonner pretty interesting from an engineering/problem solving standpoint (here is a Youtube video of his GE in action: http://www.youtube.com/watch?v=-KYPCfBCJcU). Now, I’m not going to lie… I like critters a lot. Although I haven’t actually seen a 25 Tonner in person, I have been around plenty of other small switchers and I really like the contrast they present against a background of North American railroad equipment, which is always very large. I got to thinking that it was time for me to start looking into a critter project.
You may remember that I had built an Alco S4 from a Shapeways print sometime ago. I tend to poke around Shapeways on a regular basis looking for new N scale items. One day, I think in December or January of this year, I discovered a little Nn3 narrow gauge GE 25 Tonner meant as a static item or flatcar load (https://www.shapeways.com/model/1175892/nn3-ge-25-tonner.html?li=shop-results&materialId=61). I thought, “Heck, if this thing is hollow I can use it as a shell and just build a mechanism for it!” I contacted the designer and he confirmed that it was a hollow shell with fixed narrow gauge axles. That was all I needed to know, I placed an order for two of those little boogers (assuming I would damage one during the conversion process) and began my patient wait for UPS to arrive.
What arrived, about two weeks later, was a pair of pretty well detailed little critter shells. Even though they appeared to have already been cleaned, I dropped them in Bestine overnight just to be sure they were ready for primer.
I slapped some paint on one shell and went to work measuring dimensions out, seemed this shell was a bit smaller than the Kato 11-105 Power Chassis components I was planning on utilizing. Some days of thought went past along with consulting with Randgust himself (via Trainboard.com) about details of his 25 Tonner build.
It turned out that I was going to need to re-dimension some things and make some changes to the Kato truck/gearbox which forms the heart of this 25 Tonner.
What I came up with was using the side frames from the 25 Tonner shell to hold the end-axle electrical pickups in place with the remainder of the chassis built up from .20 styrene sheet (the same material used by Randgust on his build).
After getting the axles and electrical pickup tweaked to a point where the locomotive would actually run, albeit rather poorly, I began ballasting the garbage out of the chassis and shell. Once ballasted it, the little critter ran a great deal better. Some Atlas/Accumate couplers, and a snazzier paint job later, I think I have something of a winner.
I need to add some details and handrails, but I basically have a decent little N scale critter at this point. It runs very well forward and acceptably backward (although I may be able to improve that with a transistor throttle). There are a few mechanical woes that plague the drive train, like a dislocated rear axle, but those only appear if the locomotive is run at high speed. It even operates through Atlas Snap switched with non-powered frogs, that isn’t bad for 4-wheel pickup/drive, so I am at least coming close to the standard set by Randgust and his 25 Tonner!
I even tried it in operations but the Cheap-O 1980’s Bachmann trainset powerpack I am currently using is just too limited for precise control. Hopefully things will improve once I retrieve my Tech II from storage or pick up a new throttle at the local hobby shop.
I hope this post serves to inspire some creativity in the same way I was inspired, there are a lot of great projects out there in the 3D printing world for N scalers with a little imagination. Take some time to browse Shapeways, or any other kit site, find something you could use on your layout and make it happen. Don’t ignore a potential project just because there is no commercial chassis available, part of what makes this a hobby is making what you can’t buy.