I have the good fortune of purchasing a new loco for my layout, however, I am undecided as to which to get. I am looking at either a SD70M from Athearn or a B40-8 from Atlas. They are both under $80 so my question is: Which would you get if you were modeling a current UP line? I have a couple of ATSF Genesis engines and love them, but I also have the a couple of Atlas locos as well. Help me out here with a choice!
Well, when it comes to modeling a modern UP line, you can't very well have too many SD70M's... If you really want something different, get the SD70M and paint it in the UP "Flag" scheme. Chris Toth
I'm going th have to recommend the Atlas unit. The Genesis SD70Ms have low profile flanges and the pair I had derailed constantly. There just wasn't enough flange there to hold them on the rail through turnouts. The layout I was running on has code 83 rail and generally very high track standards. On the other hand, I've never had any problem with any of the two dozen or so Atlas locos I own. Just my $.02 worth.
You sure about low profile flanges on the Genesis SD70M's? All the ones I have and have seen have standard RP25 contour wheels; the only Genesis rolling stock to have semi-scale (.88") wheels, and advertised as such, are the various 60' Hi-Cubes, the Trinity 5161cu.ft. covered hoppers, and the new 50' SIECO boxcars. The derailing problem with your SD's may stem from a documented problem with warped trucks; early runs of the SD70/75's had this problem from the factory. Place a truck on a piece of glass, or a mirror, and check to see that all wheels are making contact. If not, you cna gently twist the truck to make sure all the wheels make contact, or you can contact Athearn for free replacements. I've been fortunate; the SD70M's I have did not have this problem, and perform beautifully on my club's layout. But back to the original question on modern UP mainline power. I'll second Chris's comment; when it comes to modern UP operations, you can't go wrong with several UP SD70Ms! With over 1,000 scheduled to be on the roster, they are everywhere on the UP system, in a variety of assignments. The Atlas UP B40-8's, on the other hand, represent former Cotton Belt units (UP never bought B40-8's on their own), of which SSW only bought 55. They were originally bought for service on SP/SSW hotshots, but on the current UP, I usually see them in general freight service; in fact, I saw one in local service about a year ago! The Atlas and Genesis units are both excellent models, but for sheer commonality, I'd have to go with the SD70M. If anything says current mainline power on the UP, they do.
