Odd issue with my layout

[RufusRoc]

Hi All,

So i put together an HO scale DCC 4x8 layout with 2 connecting ovals (22" and 18" radius curves, which are slightly super elevated) and a yard setup in the middle with 3 turnouts. I'm using an NCE Power cab and have the power running with terminal rail joiners to three parts of the layout from the controller.

Anyway, I started running a few of my locos to test it out (all have DCC decoders). When i ran my Bachmann Acela Express loco at low speed, it kept slowing down, sputtering and sometimes stopping on the same 2 sections of the layout, while it ran fine on the rest of the tracks. These sections were each 18" curves diagonally across from each other on the layout. I cleaned these parts of the track and the wheels on the loco itself, and even tried adjusting the decoder, but the issue keeps occurring. When i increase the speed, the issue isn't noticeable. I have 2 other Rivarossi locos, that run perfectly without any slowdown on these sections at all speeds.

Anyone have any thoughts on what the problem might be? I'm at a loss right now. It seems weird that only one loco seems to be affected at only 2 specific parts of a rather small layout.

Please help!

Thanks!

[otiscnj]

How many power feeds do you have to the track? If you add feeders in these locations, does the same thing still happen? Also, did you mix up the feeds? The fact that it happens on opposite sides of the layout is a clue to whatever is wrong. Is it a problem for all of your locos, or just the acela? I'm not into DCC, but my first guess is that you need more feeder wires. How many amps does your powerstation put out? Maybe its underpowered, but I'd go with more feeders, first.

Good luck!

[RufusRoc]

Hi, I have 3 power feeders to the track from an NCE Power Cab, which has 2 amps. One section is connected very close to a feeder as well. I don't think the feeds are mixed up, because my other locos run perfectly fine on the layout

[dave1905]

Unless on a tight curve the trucks loose contact with the rail or the mechanism binds or otherwise loses contact on curves or on the superelevation.

[MGWSY]

The Bachmann Acela and HHPs dont like superelevated curves as the trucks dont pivot much side to side. I bet its either binding or losing contact at slower speeds, faster speed allows it to coast through the curves but I wouldnt recommend running them on 18" curves anyways.

[Mark R.]

I agree with the above .... 18" radius is pushing the limits for the Acela to start with. Super-elevating the curve will make it even worse.

Try flattening out the curves first and see if that makes any improvement. Your problem is NOT electrically related to your NCE system.


Mark.

[RufusRoc]

thanks for the help guys. I think I'll try tinkering with the super elevation or running it on 22" radius curves.

By the way I'm kinda new to the hobby, and am tryinh to learn all the lingo, so what does HHP mean?

[TrinityJayOne]

That would be the HHP-8, an electric loco used by Amtrak.

[Selector]

It could be that the locomotive trucks are near their limits on the inner curves and that wheel flanges are rubbing against something, but not so hard that it lifts the loco out of the rails and causing a derailment. I find that modern diesels' trucks, at least in Athearn Genesis SD-75M cases, don't like much superelevation. Or, if you really want it, it must be gradual and on sweeping curves. No in and out of supervelation over just 10-15", for example.