In case you're curious, you can see an exploded parts diagram of the AHM version of this same engine at http://www.hoseeker.net/AHMRivarossiassembly/AHM060sidetankpg2.jpg.  The only difference is the style of side tank.

Another good photo of what I'm going for comes from a 1943 Porter catalog:

The main difference between the photo and what I'm going for is that my model will have inside Stephenson valve gear.

I paid about $11 for the model on ebay, knowing that it would be little more than a running chassis.  What I received was even worse that I expected, having no bottom plate and various cracks in the frame.  Still, it seemed like a repairable model, the quality of the parts that I actually wanted is decent, so I figure I can do something with this.

I started by removing everything that didn't look like a Porter 2-6-0, including that rather large motor.

Not much left, is there?

With this much of the engine to build, where to start is far from obvious.  I decided to start with the running boards, and then work up from there.  I found a brass tube that would just accept the smaller motor I have on hand, and started figuring out where to put the various parts.  As it turns out, there is a step in the frame which is at about the right height for a running board, so that makes a good level reference surface.  I cut a combination running board and cab floor out of .032" brass sheet, since an engine this small needs all the weight it can get.

Here it is, along with the new motor:

The bar soldered to the bottom both locates the piece securely and supports the rear of the motor.  At this point, things are just stacked up loosely to see how they fit together.

There should be enough room for a Digitrax DN135 in front of the motor.  I still need to figure out exactly where and how to mount the boiler.  The motor will probably be simply taped or glued into place, but that is also to be determined.

Here are the parts I have so far, more or less laid out as they belong in the finished locomotive.  The tender tank will need to be shortened or a new one made, but that's a project for another day.

Ken,

I rebuilt a old Tyco 4-6-0 once. It was on the light side, so I replaced the bottom plate with a piece of sheet lead. it helped a lot with the engine's pulling power. That engine had the poorest excuse for a motor, oh wait i forgot about the pancake motors in the old Bachmann 2-8-0. The hotter they got the slower they went.

Anyway just a suggestion, since there is little room for weight. Just don't tell the EPA.

Regards,

John

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If there are no stupid questions, then what kind of questions do stupid people ask? Do they get smart just in time to ask questions?  >> Scott Adams

Thanks, John.  I had thought about styrene (easy) or brass/steel (harder, but heavier), but not lead.  I like that idea.  I have a bunch of lead sitting around, and I'm thinking of trying to cast a custom weight to fill as much of the boiler as possible.  Now that you mention it, a lead bottom plate makes a lot of sense.  I think I'll try that.

This promises to be great!  I like your choice, Ken: it will be a great challenge.  I would have gone for a chubbier body based on the weight, but obviously you are discarding that...  I am curious to see what you end up with.

To secure the motor get some spring wire and bend it to the shape of the motor as it sits; engage the bent ends below the floor.  If you bend the wire exactly right you should end up with two "u straps" that want to spread open but are restrained by the brass frame, and keep the motor snug.  The same can be made with a single, wide, spring steel strap.

Interesting idea.  My original plan had been to solder the boiler to the running boards, but the more I think about it, it would be better to make them separate.  That way, I can mount the motor, decoder, etc. on the frame, and then just set the boiler down over them.  The way I made the running boards, with the shelf for the motor to sit on, the motor ends up being captive if I solder the boiler in place.  I really like your suggestion of a spring clip, and I think I have the perfect material and location for it.  I'll see what I can come up with.

As far as the weight, I have not yet built the boiler, so I could make it as large as I like, but I'm afraid it would be out of proportion and ruin the lines of the engine.  I'm confident that I can hide enough weight in there to make it handle 2-3 cars reliably, and that's about all that the prototype would have been asked to move.  If an N scale locomotive can be made to work well, then I ought to be able to pull it off in HO.  That's why I'm working in brass this time, though.  I need all the extra weight I can get.

Ken,

If you find that a more powerful motor is needed, I have used a couple of motors from Jameco. The are in the $3.00 to $10.00 range. The company has data sheets on line that give current, voltage, RPM, Torque, and dimensions. They have several that are in the 12V range and less than an inch in diameter. they only sell single shaft motors, but these are good for most steam engines.

I usually run the motors for an hour in both directions and check for defects, I make it a point to buy at least 2, so I have a spare. The motors I have used are cheaper than a brush set for my older motors.  The 232144 and the 231732 parts look like good candidates. The motor stock changes, so you may not find the same motor in 6 months. The bad news, I have purchased a motor from this vender that was not suitable, but the good news is most of their motors were good performers.

http://www.jameco.com

Regards,

John

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One of my favorite philosophical tenets is that people will agree with you only if they already agree with you. You do not change people's minds.>> Frank Zappa

First of all, thanks for the suggestion on the motor mounting clip.  I made one and installed it, and it looks like it'll work fine.  I need to tweak it a little, but I expected that.

I made a boiler and smokebox this afternoon, and (after realizing that the smokebox was drooping and re-soldering it) I discovered that the boiler is going to ride rather high.  Maybe too high - I'll have to clean things up a littler and see how it will look in its final place.  I may end up making a larger boiler, just so that it can appear to sit lower.  The top height is dictated by the motor, but a larger tube can have its center lower and still work.  I'll have to balance small boiler vs. low boiler.

No pics yet, I have to get ready for work.  We'll see how it looks when I get home in a few days.

Camelback?  Good for hiding the high motor, but bad for most prototypes!

Ugh..  What a funny concept, a Porter camelback industrial 2-6-0

I need to sit down and sketch the engine, to see if this is going to work.  If not, I have two realistic options as far as I can tell.  One is to increase the boiler diameter, as mentioned, though I really don't think that will look right either.  The other is to go back to a tank engine, since the tank can hide a much larger motor, or allow the boiler to sit much lower.  A quick measurement shows that the top of the boiler sits about 10'6" above the rails, so there's plenty of room for all sorts of tanks up there.  I'm guessing that a loco like this would have been about 13'-14' tall over the cab roof and stack.

What I am really hoping will happen is that when I sketch the model in CAD, I'll decide that it's not as out of proportion as I initially thought.  It would be nice not to lose the work I've already put into the model.  Plus, I was just starting to get used to the idea of having a tiny 2-6-0 putting around the layout.  I may even decide that I like the idea so much that I scrap the model and use the motor and drivers to make one from scratch.

Stay tuned...

Well, Plan A didn't work out so well.  Since I don't want to give up on this project, I needed a Plan B.  As I mentioned above, I had some ideas, but nothing jumped out at me.  I was going to make new frames out of brass and scratch build a loco using the drivers and rods, but I decided to hack up the Bachmann frame, figuring that I have nothing to lose.  There's not much left, but at least it keeps the axles at the right spacing.

I am ditching the internal gears which powered each axle, and driving the rear axle directly off the motor.  It'll be fast, but hopefully I can control it with decoder programming.  As it turns out, the frame already had a nice flat spot at the perfect height to set the motor, and the motor I'm using is exactly the same width as the frame.  Sometimes things just line up nicely.

So, without further ado, here's the newly modified frame, along with the likely candidate for a boiler, and a shot of just how much I had to remove.  Compare it to some of the earlier photos!

I am hoping to be able to salvage the original electrical contacts and the plastic side pieces which held them in place, especially since those pieces have the crosshead guides cast into them, and it would be nice to retain those.  I'll have to figure out how to make and mount a new front frame section, but I don't think that will be too bad.  Also, it turns out that the axles snap into the frame so tightly that I might not have to bother with a bottom plate at all.  We shall see.