A question about radius

[ramoutandabout]

I finally have my trainroom / recroom done.  I'm building it 12X19 area.    Planning on building the "Red Rock Northern" found in MRR June 07.  Its size is 9X11 in the mag .  Yes it is Ho. So im plannin on using 24 or 26 radius. Ok so here is my question how will passenger cars look and operate on 26*.  Does anyone have any pics of them on both 24 and 26  radious?   I'm plannin on the transional era.  

Since i got hurt at work fractured some ribs falling of a pole and landing and a fence pole. I have to to sit and read lot the next few weeks. 

 

thanks again guyes

 

ray

 

[jeffrey-wimberly]

Passenger cars should look OK on 26 inch radius. There will be some overhang but nothing compared to what I'm used to seeing on my 18 inch radius.

[gandydancer19]

Since it is a small layout, and if you haven't got the passenger cars yet, you might want to consider using 60 foot passenger cars instead of 80 foot ones.  This will allow you to have more cars for the same length train, up to a point, plus the 60 footers will look better on the curves.  My layout uses 18 inch curves in some places and I have decided to use 60 foot passenger cars.

[selector]

Not the best view for your purposes, but the cars in the distance are Bachmann Spectrum heavywieghts on my turning loop.  It's radius is just over 24".  I find it quite tight and would expect that in the real world such an arrangement would never happen.  On my layout, it takes place below 15 scale mph.

[markpierce]

I'd limit passenger cars to a 60-70-foot length.  Avoid those that are longer for appearance and operational reasons.  Check out NMRA's recommended practices at its website.

Mark

[markpierce]

I'd limit passenger cars to a 60-70-foot length.  Avoid those that are longer for appearance and operational reasons.  Check out NMRA's recommended practices at its website.

Mark

This begs the question as to what is a 60-foot (or whatever) passenger car.  The length of a passenger car is usually measured by the length of the end sills.  This doesn't include the vestibules, if any.  A 60-foot RPO/baggage car with no vestibules may be 6' 1 1/2" long  and 62' 11 5/8" coupled.  A 60-foot coach with two vestibules may be 59' 10" long and 67' 8 3/4" coupled.  (These examples come from specific S.P. prototype cars.)  Some passenger cars only had one vestibule.  This was more common with combines, lounge cars, sleepers, and such.  So, for example, a nominal 70-foot car with one vestibule will have a shorter coupler-to-coupler length than one with two vestibules.

Also, from a modeler's view, a car with three-axle trucks is likely to require a larger radius than one with two axles because there is a greater likelihood the trucks will foul underbody details unless they are removed or modified, if not already done by the manufacturer.

Mark

[wjstix]

Walthers recommends 24" radius for their full-length (80') passenger cars with body mounted couplers. My last layout had one section of 22" radius curves (freight only...well, ore cars really) that I used to test passenger cars on. Rivarossi 80' cars with truck mounted couplers would do it with no problem, but none with body mounted couplers - even 60' cars.

Keep in mind that not all passenger cars were 80' long. Heavyweight RPO and baggage cars were usually 60'-70' long, and coaches were usually 70' or so. Athearn's RPO, Baggage and Coach cars are "full size" for example, even though none of them are 80' long, since the real cars weren't 80' long either. Athearn cars have truck-mounted couplers and will go down to 18" curves. Athearn also makes other cars that are shortened from 80' down to about 72'. Rivarossi also makes/made a 70' coach (with truck mounted couplers).

Anyway, you should be fine with say 26" radius curves. My previous layout had 28" min radius and I could run a train of Wathers Superliners with no problems. Of course it would look better with broader curves but that's always true...stuff looks better on 40" radius curves than 30" radius etc.

[Texas Zepher]

here is my question how will passenger cars look and operate on 26*.

As the others have pointed out it will depend on what is meant by a passenger car. 

For looks, I figure if I can see the outside ties or worse the rail in center point of the car, the curve is too tight.  In my opinion 80 foot cars start looking tollerable at about 30" and look Ok at 36".  They look great on 40" or higher.

Athearn has a series of shorties, and Rivarossi recently ran as set of 60 footers.  

As for operation the for the Walthers heavyweights (and six axle lightweights), their minimum is 24" and even at that the instruction sheet says, "For improved operations on a 24" radius curve, trim the cneter sill to clear the wheelsets."  I don't have any curves that small but I would assume that would be good advice for 26" as well. 

 

 

[jrbernier]

Ray,

  If you are going to 'expand' a 9x11 layout to a 12x19 foot area, why are you planning on using 24/26" radius curves?  I would expect that you should be able to work 30" radius curves in the plan.  One of the problems you will find is that a 2" separation between the tracks will not be enough to prevent 'side swipes' with long cars(those passenger cars).  The NMRA suggests at least a 2 1/2" track center for running full length passenger cars on anything less that 32" radius.

  Our club layout has a minimum radius of 33"(inner track), and we use a minimum of 2 1/2" track centers.  An articulated engine on the inside track does not 'side swipe' a train of full length passenger cars on the outer track.

  My home layout has a minimum for 22" radius curves and I use a mixture of Walthers 60' passenger cars, and some Con-Cor 72' passenger cars.  A test with a siding to the outside of the main line(with 'about' 2 1/4" track centers on the curve) showed that I was cutting it very close.  Normally the siding will have 40'-50' freight cars on it, so I appear to be safe. The planned 'future' layout will have nothing less that 30" radius, and 2 1/2" track centers on curves.  I do not want to 'side swipe' my new Walthers 'Hiawatha'!

Jim

[R. T. POTEET]

The National Model Railroad Association standard for curve radius specifies a radius equal to three times the length of the longest car being operated. If we assume that to be eighty-five feet then we take 85 X 3 X 3.5 X .03937 which comes out to a resounding 35 1/8 inches. If you were to go with sixty foot OK Streamliners then we take 60 X 3 X 3.5 X .03937 which comes out to a resounding 24 13/16 inches.

What does the NMRA know? they know how to keep the trains on the track and make them look intelligent doing it!

[steemtrayn]

60 ft. cars on a 26 in. radius curve:

Full length cars on the same 26 in. radius curve:

[IRONROOSTER]

To clarify, the NMRA has no standard, but does have a Recommended Practice for curvature here http://www.nmra.org/standards/sandrp/rp-11.html  This specifies 32" for 80' cars with diaphragms, 23" for 60' cars with diaphragms, 20" for 60' cars without diaphragms. Note: this is for restricted speed operations.

The Layout Design SIG recommends 3 times the actual length of the car over the couplers for good operation (4 times for appearance) http://ldsig.org/wiki/index.php?title=Curve_radius_rule-of-thumb or 36" for 80' cars and 27" for 60' cars.

Enjoy

Paul 

[Anonymous]

A couple of cautionary notes:

1.  I recently purchased a set of Roundhouse 50' Overland cars (http://www.roundhousetrains.com/Products/Default.aspx?ProdID=RND84831).  Their length, coupler to coupler, is actually 8.25 inches (60 scale feet).  So don't rely on advertising alone.

These cars work and look fine on 27/28" radius but I found out that the steps on the ends of the cars had enough of an overhang coming out of an eased curve to hit a Caboose ground throw. So:

2.  Look for other possible obstructions that may effect your operation with long cars.

Good luck,
-John