# SD70-MAC



## James Kuhns (Jan 12, 2008)

I am sure I will be told that I should not try to run the SD70 on 4 foot radis curves, but that is what I have on my railroad. Here's the problem. The engine runs around the railroad with just fine but I can not get the following freight car to stay on the track. I have worked with coupler lengths and even use one of Bachmann's 20' freight cars with body mounted couplers (believe it or not that is the one I had the best luck with). I use USA Trains couplers on all my rolling stock. If anyone has a solution I sure would like to hear it. 

Thanks, James


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## Guest (Aug 9, 2008)

I think its just to tight of a curve,even with pilot mods, i don't think it csn work reliably on anything less than 5ft radius/DesktopModules/NTForums/themes/mls/emoticons/w00t.gif if you figur it out, let us know ... 
Nick.....


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## W3NZL (Jan 2, 2008)

Jim, 
I can tell U how to do it using body mount Kadees, but since I've 
used nothing but Kadees for over 50 years, I have no idea what it 
might take for other types of couplers... 
Paul R...


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## castlebravo (Jun 9, 2008)

A couple of questions I would be asking myself. 

Is it every car on every turn or just a couple of cars on one turn? 

Is the turn an "S" curve? 

Do the couplers run out of swing? I would run the loco slowly around the trouble spot and stop it to check and see what is happening. If they are not running out of swing are the centering springs too stiff to allow full travel? 

Good luck finding a solution.


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## James Kuhns (Jan 12, 2008)

I have done all of the above. I think I have found the solution and it is not any of the normal ones. I will let everone know when it proves out.


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## aceinspp (Jan 2, 2008)

Guess it would be called wider curves Later RJD


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## James Kuhns (Jan 12, 2008)

I found a solution for pulling cars behind the USA Trains SD70 on 4 ft. radis track curves that works for me. Pictures are on Gregg Elmassian's web sight. http//wwww.elmassian.com If more information is needed on how to do it let me know. I have found a USA Trains modern tank car with the long coupler tang works best as the car coupled to the engine.


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## Greg Elmassian (Jan 3, 2008)

I have James' pictures here: 
http://www.elmassian.com/index.php?option=com_content&view=article&id=276:sd70&catid=14:motive-power&Itemid=318 

James and I need to beef up the descriptive text, but you can get the idea from just the pictures alone. 

Regards, Greg


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## 6323 (Jan 17, 2008)

I've been looking at the Rio Grande heritage unit recently released. 
How well does, or will, this unit run on 8 foot Diameter curves? 
That's about as large as I can go, because of space limitations.


Could go much larger, but then I'd have to go around the house completely! 
And I don't think my folks would go for that!


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## James Kuhns (Jan 12, 2008)

4 foot radius and 8 foot diameter are the same thing and as noted above I have gotten this to work very well with the modifications I did to my locomotive. 
Only one thing, I have much better luck pulling a USA Trains modern tank car behind the engine than other cars I have.


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