Who says 18" curves are unrealistic?

[rrinker]

 Keep in mind though that these are all specialty trackage, usually for an industrial lead, and NOT a place where mainline 6 axle SD70ACE's roar through with a mile long freight at 50MPH.

              --Randy

 

[canazar]

I love photos like this.  It helps to me justify all the crazy things I want to do that drives a few of my rivet counter freinds crazy.   "See, prototype!"  No matter how wild a modeler will think, someone in the real world has done crazier.   

[DSO17]

     There was a factory along Conrail's former PRR Washington Ave. street trackage in South Philadelphia that had a very sharp curve leading into it. 50 foot boxcars would not go around the curve coupled to the RS3ms (Alco RS3 rebuilt with an EMD 1200 hp prime mover) Conrail was using at that time. Empties were pulled out of the building around the curve using a cable. Inbound loads were kicked off the street around the curve and then the RS3m would run light around the curve to couple up and spot the car. If a car being kicked hung up on the curve, the cable would be used to pull it back out into the street to kick it again a little harder, but not so hard as to go through the back wall of the building.

     Sometimes you gotta do what you gotta do...

[Wulfblat]

Here's the Google Maps link for the image:

Portland Steel Bridge

As another poster has pointed out, scrolling about the map reveals a lot of interesting track work because the UP and BNSF yards are nearby, as is Union Station, which is just across the Steel Bridge and the tower of which is visible in the original photo, just under the arm of the leading crane on the ship.

The Steel Bridge itself is interesting in that it is a dual lift bridge, with the bottom span for the railroad able to lift independently of the top span, which is for traffic and light rail. There's a walkway on the south side of the bottom level that connects the east esplanade with the river front park on the west side.

 

 

[accatenary]

Assuming the Covered Hopper in the Picture is 58' coupler to coupler I would say that that radius is tighter than 18" in HO scale. To complete a 180 deg. turn you need 261' feet diameter. If the width of the grain silos is 60' ,you  should be able to fit 4 grain silos structures within the inside of the curve and still have 20 feet . Looking at the picture only three grain structures will fit.

[BRAKIE]

ericsp

I can't help but wonder if the photographer was guessing about the track radius. American Railcar Industries lists the minimum radius for its 4250 cubic foot covered hopper as 150 feet. An 18 inch radius HO scale curve is 130.5 feet for real trains. Also, the 4250 cubic foot car is shorter than the car in the photograph.

 

When I worked on the PRR there was a lumber company wedge between 2 larger industries..The curve(probably less then 150') was restricted to nothing larger then a switcher such as a SW7 or S2 and 40' boxcars..

Even at that we would not exceed walking speed and  both brakeman would walk along the side and watch the trucks for possible trouble..The flange squeal was unbelievable.

 

[ericsp]

I can't help but wonder if the photographer was guessing about the track radius. American Railcar Industries lists the minimum radius for its 4250 cubic foot covered hopper as 150 feet. An 18 inch radius HO scale curve is 130.5 feet for real trains. Also, the 4250 cubic foot car is shorter than the car in the photograph.

[Eric97123]

I live in Portland and looking at the googl maps it is a great place to model.  if you follow the tracks from the UP yard you can see all kinds of sidings that would make a great model layout.  There is even a nice long tunnel from the UP yard that runs under the North Portland neighborhood.  I bet most folks done even know they have a train running under their house.

[Dave-the-Train]

jmbjmb

Just for the heck of it, I went to Bingmaps.  The whole area looks like an old school, bowl of spaghetti track plan.  That's not the only loop there.  There were other loops within loops, you name it.  Yep, whoever designed that track plan sure didn't use a linear shelf layout. 

Any chance of the link please?

[Bill H.]

How slow? Probably not much more than walking speed, as they are not likely to be moving the cars very far anyway.  Industrial settings are purpose built with no points awarded for appearance.

[AltonFan]

It's worth remembering that in some really tight situations, cars would be uncoupled and pulled with chains.  I imagine poling might have been helpful in some tight curve situations.  I wonder of in some places very short idler cars were assigned to certain tasks.

[jeffrey-wimberly]

Just shows that there's a prototype for everything. There's a sharp curve near here that goes around the lumber mill that works out to about 22" radius. The big locos (AC44's, SD70's) can take it OK but no faster than 40 mph. This is on the mainline, not a spur or siding. The KCS has the grease the inside edges of the rail heads twice a day to keep the traffic from tearing the rails to pieces. Even so the cars set up a horrific shriek when going around the curve.

[SRN]

It's interesting to contrast the trackage in that photo with Norfolk Southern's current industry track minimum radius requirement,  462 feet. What a difference. Not that NS serves Portland, OR, but I happened to have recently looked at their customer owned trackage requirements.

 

 

[wedudler]

You mean street running, like this?

Wolfgang

[tomikawaTT]

The 'bridge' noted by the poster above is actually the ship-loading conveyor, which enables loading of the commodity along the entire length of a bulk carrier.

 

It is definitely possible to justify tying your trackwork in knots if you pick your prototype with care.  The Uintah (original home of the Mantua 2-6-6-2T) had curves that scale down to 12 inch radius in HO.  Way back when, street railroads would fit coupler extenders on the then-standard forty footers and use their radial-coupler-equipped box motors to snake them around street corners.  My pet prototype ran 4-wheel hoppers behind 4-wheel steeple cabs on dual-gauged streetcar tracks to reach the wharf in Hakata port where coasters loaded the output of the local collieries.  (The steetcars were standard gauge.)

 

BUT!!!  Note that none of these were operated at track speed by stiff, long-wheelbase locomotives.  About the only part of a Big Boy that can round curves of this nature is the pilot truck - detached from the rest of the locomotive.  As for Pullmans and humonguboxes, fugghediboudit.

 

Chuck (Modeling Central Japan in September, 1964 - with some very tight curves)

[R. T. POTEET]

 

Is that a 4-8-8-4 Trackmobile or a 4-6-6-4 Trackmobile?

[jmbjmb]

Just for the heck of it, I went to Bingmaps.  The whole area looks like an old school, bowl of spaghetti track plan.  That's not the only loop there.  There were other loops within loops, you name it.  Yep, whoever designed that track plan sure didn't use a linear shelf layout. 

[NittanyLion]

richg1998

Try that with 85 foot cars, or maybe a SD 70, Big Boy, etc.

Rich

There used to be a curved track back in my home town that was so tight that Pullman used it to test the now common 89' flats on when they were still under R&D.  They easily derailed on it for a long time before they figured out something about how the cars twisted under force.  It probably wasn't much broader than the curve in the foreground of that picture above.  They didn't run anything much bigger than second generation Geeps and ore jennies on it either.

[trainman6446]

I love the bridge on the left side of the photo. I wonder if this complex was built when 40' boxcars were the norm.

[Texas Zepher]

I do!  It looks interesting but still silly even in the prototype.   In fact, it highlights how small 18" radius curves would be in real life.  And we still have people who get angry when their big boys don't go around them smoothly.   go figure....

The tightest curves I've seen in non-industrial tracks were the 24 degree curves on the Monarch Branch of the D&RGW.  An SD9 could not navigate them and they had to run 4 axle locomotives on that branch.

[tbdanny]

Hamltnblue,

I must admit that the link to that photo was sent to me by a friend and fellow model railroader - I just thought you guys would like to see it.

Cheers,

tbdanny

[Hamltnblue]

Trolley cars and small switchers navigate even steeper curves. That is a good find though.

[richg1998]

Try that with 85 foot cars, or maybe a SD 70, Big Boy, etc.

Rich

[IRONROOSTER]

Thanks for sharing.

I wonder if the railroad did anything special for that curve like widening the gauge or modifying the couplers.  I also wonder what speed they're moving.  I know it's real slow but how slow.

Enjoy

Paul

[galaxy]

Nobody says they are unrealistic, they just don't work that well for longer locos or cars on the models.

There  really is a 'prototype for everything" just the models may not work as well as the real life situations.

I've seen some pretty tight curves that real railroads navigate s l o w l y  but on a model it may not work.

[steemtrayn]

Can real locomotives take that curve? Or just Trackmobiles?

[tbdanny]

http://railpictures.net/viewphoto.php?id=339228&nseq=0

The caption makes a comparison to HO scale curves.  Just goes to show, if it's done on the model, it's probably been done in real life