Roll your Own

If Kato or Athearn won't produce the models needed for the Allegheny Eastern I'll take a shot at creating my own. N scale PRR modelers have been doing it for a while now. It's more fun. It's also cheaper if you use the right priced parts. Locomotives like the BP20 passenger "shark", the H class 2-8-0, or the giant BP60 have to be cobbled together i.e. "kitbashed".

Which brings us back to the current obsession, the BP60 "centipede" I'm creating for 3D printing...

PRR Class BP2 (BP60)

I started this crazy project and now I am determined to see it through come hell or high water. Shapeways wants it hollow. Well alright then, it's hollow...

Inside The BP60 "Centipede"

I'm not really complaining, though I do wish I had stayed in the garage and laid some track. It was a challenge to hollow this beast out. Along the way I also developed a whole host of techniques for making these "CAD" drawings easier and more accurate. Little hard to explain, but the picture may give you an idea of the results.

Right now I'm waiting on 3D Canvas to munch it's way through the translated file. I'm trying to see if I can "solidify" the model using the utilities in 3DC. It's taking forever, probably owing to the complexity of this beast. With almost 61000 Vertices and about 92000 polygons it's the most detailed model I've ever made. Train Simulator doesn't really tolerate complex objects. As a result I had to learn how to do things in the simplest way possible. This is exactly the opposite.

PRR Class BH50

The Pennsy centipedes were configured quite differently than their cousins. The most obvious difference is the lack of "portholes". The only porthole on a BP60 is in the rear door. The BP60's also have the louvered roof panels that other centipedes lack. I tried to make the model as Pennsyesque as I could. I used photos of the real thing as well as models by BLI, Lionel and anybody else who's attempted to replicate these monsters. I have detailed drawings, but not of the Pennsylvania version. I do have the PRR drawings, but they are more of a schematic that an actual plan...

PRR Drawing E437703-R-RC

It did give me locations for items like the water and fuel fillers as well as the sand hatches...

Fuel Filler (Red) and Sand Hatch

Water Fillers (Dark Blue)

I show louvers, but they don't exist on the BP60. They were on the detailed plans (Seaboard #4500, the first DR-12-8-30). I'll be deleting them before the file goes back to Shapeways. While these small details are nice, it's very likely they will disappear on the finished model. The CAD version shown here is technically full size and measures about 80 feet long. It will be printed in N scale, 160 times smaller.

The biggest problem in preparing the model is making it what Shapeways calls "watertight". Basically this means there can't be any "holes" in the model mesh. The "holes" can be filled using software that allows you to edit the mesh. Unfortunately, using the "fill holes" function tends to fill in things like window openings and such. It took a few days to figure out a way to solve this and the solution is tedious to say the least. I fill all the holes and then reopen the windows, intakes and the like. Great fun! Lucky for me that the software highlights what I need to remove. Selecting the offending blockage is easy. point click and TADA!...wait while the program completes the process. It takes quite a while for each deletion to complete and there are a lot of them...

Highlighted "Blockage" in an Intake Opening

In other news, I've been buying up mechanical parts for the model. I was able to snag two more Bachmann DD40 models on E-Bay. I got two of them for less than $30. I now have enough parts to build two centipedes with two power trucks each. The only misgiving I have is the Bachmann motors are three pole without skewed armatures. These older motors tend to "cog" as they rotate at slow speeds. I have some inexpensive Life-Like motors with skewed armatures that will run a lot nicer. There's a problem, however, in "swapping" them for the Bachmann's. While the motors themselves are the same size, the Life-Like motors have external bearings that may or may not cause problems with the gear alignment...

Motor Swap

Hopefully you can see the thin blue lines in the image above. These mark the outer ends of the bearings on the Life-Like motor. You can see that this would push the worm gears way out from the drive gears. While there is some degree of adjustment, it may not be enough.

In other news, I've been working on building up the steam roster on the Allegheny Eastern. I recently purchased a bunch of Minitrix steamers off E-Bay, including a couple of 0-6-0 switch engines. These models are supposed to resemble the Pennsylvania's B class. While they may, the real reason I purchased them is because they also look a lot like the PRR's Consolidation (2-8-0) or H class. Most of the later H's were short and stocky. The only side view I could find of one is of a model H10 but it gives you a good idea of the appearance of these little beasts...

H10 Model

I've read that many modelers use the Trix shell to model the H. The cab is combined with the boiler of a Trix K4s to create a better looking replica. I myself have no qualms about using the Trix switcher shell just as it is. Aside from the dome arrangement and a slender boiler the short length looks good on the 2-8-0 running gear. Thanks to the wonders of Paint Shop Pro I can show you what I mean...

N Scale H Class "Kitbash"

With the proper paint and smaller lettering it will make a passable H class. Both of the switcher shells I own are cast metal, not the plastic used in later versions. It's a Zamac alloy or something and would be murder to try to cut, even with a power tool. Best left alone. The running gear is actually from a Mikado (2-8-2) I had laying around. The motor is absolutely too long for the swap (I cropped it out in the image). I may end up finding another chassis for the thing. Since I plan to build two of them I should matching mechanisms. The old Bachmann Connie, modeled after a Reading engine, is supposed to be a good candidate.

That's all the madness for this week,

Regards

Frank Musick

Chief Cook and Bottle Washer

Allegheny Eastern Railroad