Lobaugh Challenger

I don't, but you would be better off with a bridge rectifier.

You can figure out the wiring - remember, reversing an AC motor requires reversing only the field or only the armature - not both.  Hence four wires are involved.

Any AC motor (series wound) is wired just like a Lionel loco from Postwar days.    You could even install a Lionel E unit in it.    I did that with some back in the 80s.     Dallee Electronics used to make electronic E units also.

So if  you can pull out an old Lionel wiring diagram it will show you how to wire.

Thanks for the replies. I've tried the bridge rectifier to convert to DC but the heat it produces worries me some. I'd like to simplify and modernize the whole system. Stripping the system down to just 4 basic wires will help, then start new with an e-unit in the tender. I checked out the Dallee e-units and that just might work plus the LED lighting options are good too.

You are going to run it on AC?  I have several of these with a $3 Radio Shack bridge - these things can take a real beating - 50 volts at ten amps or so - that power level would burn up your sewing machine, let alone a Lobaugh.  But the bridge only works on DC - you will need the ACRU or whatever they call them to run AC.

Put a bridge in there, then put a bridge on your transformer and a reversing switch.  cheaper and way easier.

How about some photos?  Here is one to motivate you:

Beautiful Challenger you have. I'll get there with this one. In Vegas now, home in a week or so and will post some pictures of the project. I've stripped it down to 3 basic pieces. Forward and rear drive assemblies. Then the boiler/cab assembly. Removed old paint and re-soldered broken piping etc. Some drive links need replaced along with pieces that I'll need to order based on what I can see from assembly prints from Stevenson. Yes I would really like to run AC because that's the equipment I have now. Mostly 3-rail but this has got me interested in 2-rail also. The Challenger deserves to be restored.

Modern?    Most most, if not all "modern" stuff since the turn of the century at least has used DC motors.    If you want modernize, get a large "good" can motor for it.    Install Loksound or Tsunami decoder.   

I think (operative word), keeping it set up to run AC is going to be a little more complicated than DC regardless of what electronics you use.    

That is true no matter what.  AC is only used in 3 rail because of tradition.  They now have to convert AC to DC on board every locomotive, instead of once at the transformer.  And the "E Units" have always been a mess.

But a hobby is what you want it to be.  Those huge motors had a charm, and act like flywheels.  If you get the correct E Unit, capable of six amps, you should be ok.  Lots of wires to the tender, though.

Do re-lubricate those gear boxes.  Parts are getting scarce.

Thank you Bob2 that is exactly right. I'm leaning toward the Dallee #1400 e-unit. A nice clean wire harness to the tender should work good.