2 rail MTH BNSF executive SD70MAC conversion to 2 rail

Through all these years, I was not aware that 2-rail could run DCS. I assumed that since the track carries the signal, three rails would be necessary. Bravo, Engineer Joe!

TMCC, DCS, and DCC are not rail-dependent. It's just a matter of one rail carrying the "hot" side of the signal and the other rail running the "common". Where it gets a bit dicey is that Proto-2 engines are polarity dependent -- i.e., that the signal can only be picked up on the "hot" side; Proto-3 and DCC don't care.

@Engineer-Joe posted:

Spent the better part of the day working on this engine. Had to finish it to see her run! Work is rough by my standards.

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I got a pair of these from KGsouth and I may convert the dummy too.

I ordered new sunshades and will paint and install them when they arrive. I thought about moving the trucks outward. I'm getting to the point where I just want them to run. I spent many hours on a Challenger upgrade, only to have her quit on the second lap for our grandson (steam pipes broke loose).

I really wanted the OMI version. I don't have the funds and can't find any samples.

Nice work, Joe. Did that locomotive come with the interchangeable wheel sets?

Ugh!! I was looking to purchase that set!

I had a set of 2 rail wheels waiting for the next conversion, I think they were from Jeff Sohn.

I wanted the BNSF executive SD70MAC ever since I saw it. There was a post of the OMI version here that I fell in love with. Maybe someday.....

Thank you, Matt Jackson: I need to think about the difference between PS 2 and PS 3 and the implications for my layout, especially as it affects signal pickup.

I forgot to share that the sunshades arrived. They are brass made by OMI I believe, from Bill Davis.

The color matches as is but the originals had some dark smudging on them. Probably from them trying to be reattached.

The shades are a hair shorter but the frame looks about the same length as the stock ones.

Joe, this looks great! Was this one of the MTH 3/2 locomotives, or was it a more involved conversion? I'd like to have one of these myself someday. Right now, there is enough out there that I am still buying that I'm willing to wait and see if Atlas will run these with the tooling they got from MTH. I'd certainly be in for several in the BNSF/BN and UP paint schemes!

it is the 3/2 version 20-2956-1

Looks great Joe! 

Very nice!