Model Railroading > Minimum radius needed for HO scale autoracks?

Was curious before I lay out a trackplan,What radius is needed to run autoracks with good sucess in HO scale?
 Thanks Much

Mike Mautner
Maryland Hts., MO

You can pull them around 24", but 30" works much better.

Ted Curphey
Ontario, OR

I use 28" or 30" and my Auto Racks including articulated cars work well.

Paul B
Canton, GA

They would look better on 36".

tomstp Wrote:
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> They would look better on 36".

Anything bigger than the minimum recommended would help auto racks to look better.  But really they need more than 36" to look good.  I had 36" on a previous layout and noticed the Walthers autoracks still looked awkward and had substancial overhang.  Later, I was at a train show watching an autorack train go around a modular layout corner and it looked quite good.  I asked one of the layout guys what the curves were.  I can't remember exactly but the radius was in the 50 inch range, 54 or 56 inches I believe.

Most home layouts don't have the space for such broad curves so we have to try to find something that will allow reliable operation even if autracks don't look as good as we would like.

36" would be fine if you had a abandon grocery store

HO scale 36" is about a 20 degee curve.
For prototypical reference, the sharpest curves on Tehachapi Pass are 10 degrees.
The Santa Fe invested quite a bit of money to realign Cajon Pass from 10 degree to 6 degree curves due to "stringline" derailments.
But I live with 36" radius curves and long pigs, passengers, and autoracks work fine.
Here is a Superliner set on a 36" radius curve.

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railstiesballast Wrote:
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> HO scale 36" is about a 20 degee curve.
> For prototypical reference, the sharpest curves on
> Tehachapi Pass are 10 degrees.
> The Santa Fe invested quite a bit of money to
> realign Cajon Pass from 10 degree to 6 degree
> curves due to "stringline" derailments.
> But I live with 36" radius curves and long pigs,
> passengers, and autoracks work fine.
> Here is a Superliner set on a 36" radius curve.


In real life wouldn't a 20 degree curve have a 10 mph speed restriction on it?

Nice western scene railstiesballast.  The passenger cars are a scale 85' while the autoracks are 89', so the passenger cars might look a tiny bit better than the longer autoracks.

Ultimately we have decide based on our space and track plan what we are able to tolerate appearance-wise.  I recall an artical where Allen Mclelland had a layout with 30 inch curves.  He didn't like the appearance of the Walthers autoracks on his 30" curves, so he chopped the autorack body down by one panel and made a fore-shortened autorack to get a better appearance.  That is the only instance I have heard of such a thing but it was his preference.

MRH Magazine did an article on curve radii vs. length of rolling stock, essentially defining categories of curves relative to the length of the car such as 2 x, 3 x, 4 x and so on and how it affects operation and appearance.  The article also commented on appearance being better when viewed from the inside of a curve vs. viewed from the outside, especially for longer cars.

Cheers, Jim



Edited 1 time(s). Last edit at 09/09/19 09:57 by SPDRGWfan.

Real western flavor on your nice looking layout.

SantaFeRuss

I have 30” minimum for the visible mainline and 24” for staging and it works for me. Would love wider/broader curves, but have to raise some kids first before I can claim the whole basement.

Nathan

Posted from iPhone

Attached pictures show Athearn NYC 1066 with two Walthers Horizon cars on outside curve with 40-42 inch radius.  Inside curve has 4 Rapido NYC RDCs on a 38-40 inch radius.  Inner tracks without trains are 36-38 inch radii.  Layout is 7 x 14.

John

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Interesting perspective, not just how the passenger car or train looks going around a curve but how two trains look as they pass each other.


DocJohn Wrote:
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> Attached pictures show Athearn NYC 1066 with two
> Walthers Horizon cars on outside curve with 40-42
> inch radius.  Inside curve has 4 Rapido NYC RDCs
> on a 38-40 inch radius.  Inner tracks without
> trains are 36-38 inch radii.  Layout is 7 x 14.
>
> John

Thank you.  RDC's are on the passing siding.  NYC 1066 and the two Horizon cars hold the main.  RDC's still have the ugly couplers and car spacings.  NYC 1066 and Horizon cars have short-length Kadee 58's or 158s.

John

I can tell you Walthers racks will take 18-inch curves with little trouble... Obviously I'd recommend bigger but there shouldn't be any operational issues...

MC6853 Wrote:
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> I can tell you Walthers racks will take 18-inch
> curves with little trouble... Obviously I'd
> recommend bigger but there shouldn't be any
> operational issues...

I've never tried my Walthers racks on anything approaching 18".  A testiment to engineering but they must look quite odd on curves that sharp.

Parallel tracks needs increased spacing when you intend to move long cars. 

The speed limit on Tehachapi is 25 mph. 

Larry020 Wrote:
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> Parallel tracks needs increased spacing when you
> intend to move long cars. 
>
> The speed limit on Tehachapi is 25 mph. 

Correction, 23 mph. Who came up with that number, I do not know. Assume it was from the steam era.

I guess that we are both correct, the limit was 25 until it was reduced to 23. 

ʎɹɹɐ˥


https://www.trainorders.com/discussion/read.php?1,4333155

The speed limit was lowered to 23 when concrete ties were installed and the superelevation was reduced or eliminated on the curves. As to raising the speed to 30 is concerned, after working that territory for many years, 25 is as fast as I want to go down that hill. 

Brian Black 
Castle Rock, CO 



Edited 1 time(s). Last edit at 09/18/19 16:53 by Larry020.