# USAT F7 & Aristo streamline coaches



## bcer960 (Dec 27, 2007)

I have finally gotten around to running my passenger train. I have the USAT F7 and 6 aristo sreamliners. I should mention that I am indoors on aristo track and running with Railroad & Co silver and Digitrax. I tried to run the train and as soon as it got to a grade which is about 3% and is on a 8' curve, the train stopped and the engine wheels spin.The engine has traction wheels, but it can only pull one coach up this hill. So, I went out and got a aristo "B" unit, speed matched the engines and now I can pull 3 cars. I took off the pick-ups to reduce the drag on the coaches. I don't understand why this is such a problem as I have 3 USAT GP-7's each with it's own train pulling between 10 to 15 cars each all with metal wheels and THEY don't even slow down on the hill.

Any suggestions would be appeciated, I see pics and movies of long passenger rains all the time.

Thanks

Ray


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## Dave F (Jan 2, 2008)

If your Aristo streamliners have electrical pickups on the wheels to power the lights, that can add a lot of drag. Much more drag than you would experience on a freight car. About a month ago at one of our train shows one of the guys in our club had a digital scale with him (fish weighing scale type thingy) and we measured the drawbar tension to move a few cars. 10 freight cars only needed about a half pound of effort. 2 streamliners required 2 lbs of force to get them to move. 

You could remove the electrical contacts, wire the lights to run on bettery power and add pin bearing trucks, but overall the weight of those extruded aluminum streamliners is the underlying issue. Factor in that the drag is compounded by a grade and curve and you may have even bigger issues.


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## Greg Elmassian (Jan 3, 2008)

Ray, take your USAT F3 (yes they are F3's not F7's, and lay it upside down in a cradle or on a piece of foam. 

Now, on each axle try this: put one thumb on the right hand wheel, and one on the left hand wheel of the same axle. 

Now, try to rotate your thumbs in opposite directions. If EITHER wheel turns, you have the classic "split axle" problem... 

The axle is slipping in the housing that is part of the gear for that axle. 

You can repair them or replace the axles. 

Also, USAT diesels are pretty light, you could add a couple of pounds (keep it to about 2) and make a difference. 

Please report back your findings, I'll bet this is your problem. 

Regards, Greg


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## bcer960 (Dec 27, 2007)

Greg, 

first your right it is a F3, this morning my brain wasn't working so well. And not to bloat you ego too much, you were right a second time... both the traction axels are slit. This is a good reason it doesn't work. 

Thanks for the heads up. When I get the new wheels I will give a report. 
Ray


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## bcer960 (Dec 27, 2007)

Greg, 

Very interesting, I know the train is heavy, but I have seen and been to people's layout and they don't seem to have any problems, and with longer trains than I. Anyway, I grew up on the passenger trains (my father was a conductor) so I have been waiting for this train to get going, and now it will. 

Thanks 

Ray


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## Greg Elmassian (Jan 3, 2008)

You locos should indeed pull better, I have 10 of them, so pretty experienced with the situation with the "split axles" ... note, it's the plastic gear housing that the axles fit into that splits... 

See my site under MOTIVE POWER... USAT.... you will see some explanatory pictures and text, both on the USAT main page and a page specifically on this problem. 

I would still like to hear the results of trying to turn each wheel on each axle, you may still have "slipping axles"... 

Regards, Greg


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