Kitbashing an On30 2-8-0 into a 2-6-2

Another project which I dabbled in in the last 4 months was my first "large-ish" conversion: turning a Bachmann On30 2-8-0 Outside Frame engine into a 2-6-2 Outside Frame engine.  The motivation was actually SR&RL #24.

At the time, this was my first experience with machining.  I used the milling attachment for my Taig lathe to do most of the work.

I started off by finding plans for #24 and printing them off at scale.

Which was then followed by ripping everything down to it's base components...

My first task was actually to address the wheels.  This turned out to be much harder than I had anticipated.  The two inside drivers are blind as the prototype was.  However, to account for this (or maybe the prototype is this way), it seems Bachmann spaced the two inner wheels closer together.  Well, when you put a wheel with a flange into a spot where a blind wheel was, the problem is they collide.

I figured there would be a simple solution for this: turn down the blind driver so that it was just small enough to clear the flange of the last wheel.  I used a Dremel cut off wheel mandrel to mount the wheel to, and then put the mandrel into the chuck on the lathe.  This worked surprisingly well.

Next up was to start cleaning off metal from the area where there would no longer be a 4th wheel.  The die cast frame was clamped into the milling attachment and cutting commenced.  Being new to machining I did a few naieve things and had to do some cleanup passes on my cutting.  Milling isn't simply a matter of throwing a bit into a tool and flipping it on.  There are formulas about bit size, tool speed, and feed speed which should be heeded.  Be safe if you're doing milling of any kind.

After about an hour or so, some of the metal around the 4th wheel was cleaned off.  I had also shortened down the wheels so that they were now functional in the chassis.

I went back and used another mill and cleaned off even more of the metal around where the 4th wheel was, almost completely eliminating any sign of it.  Here's a shot of the chassis by itself after I repainted everything.

And that's about where this project stopped, because I realized I now had a big problem with the engine: It was too rear heavy.  In addition to having a die cast frame, the 2-8-0 also has a die cast cab.  Removing the last axle leaves nothing under that cab supporting that weight, and the engine can easily do a "wheelie".

This is a solvable problem, I suppose.  I imagine a set of trailing trucks on a spring could fix this, somehow.  But I'm not at that level yet to solve it.

So I set this project aside until I've figured out a way to fix that.  In the mean time, I realized how funny Maine 2-foot equipment looks when it's gauge is actually 30 inches...