Yeah, metal wheels and free rolling cars are a real nuisance. Who cares about rolling resistance when you pull 8 car trains. The slightest imperfections cause cars to settle in the low spot. Give me old school plastic wheels any day.
The point of the slope in a yard or a siding is to keep the cars contained therein.
Spurs that have slight unintentional slopes the wrong way are a hazard.
That last few inches of benchwork could be shimmed upwards.
I remember MR had and article by Pele Sorborg(sp?) using different thicknesses of hobby store foam to create a yard lower than the mainline. I do not have access to the archives.
Woodland Scenics suggests using minimum 1/2" thick risers (they would do so, of course) to allow for below grade scenic effects, track side drainage for example. An alternative to lowering the yard is laying the yard directly on the benchwork surface, be it plywood or foam, and laying the main line on such risers to get the separation of grade effect.
That 1/2" should be about three feet scaled up to prototype.
You still need to solve the incline problem resulting from the grade separation.
I am grateful for all of the great comments and suggestions made by so many of you in such a short period of time. It seems that more than a few of you prefer to maintain the yard at the same level of the mainline, while retaining the appearance of grade level.
I had not considered this approach where the mainline ballast provides the look of a mainline higher than the appearance of a grade level yard. I like this idea a lot, but to accomplish that I would have to rip up the entire yard to lay down cork like I have as the roadbed on the mainline. So, I have to think that over before undertaking that approach.
Rich
What got me started on all of this was an experiment to use my existing freight yard as visible staging. If I eliminate my engine servicing facility, or at least the turntable and roundhouse, I need an alternative site for my steam engines.
So, the thought was to keep the steamers in the staging yard connected to strings of freight cars. Since the yard is stub end, I would back the steam locomotives into the staging yard. That led to some derailments on the first turnout on the yard ladder. That turnout is not perfectly level as it slopes down toward grade level.
So, I began to consider alternative methods to keep the yard ladder level.
Rich
Does it derail at the end of the inclined turnout where the track transitions to the lower horizontal yard tracks? That’s where I predict any problems would occur.
We had a troublesome crossover at the end of a downgrade using Peco #8 turnouts. I diagnosed the fault as ending the downgrade too close to the entry to the crossover. Long wheelbase locomotives would derail on the points. Moving the end of the downgrade further away from the crossover by just a small amount solved the problem.
In another spot where we could not move the grade away from the turnout we instead moved the downgrade completely under the crossover so it was flat but not horizontal.
The derailments only occur with steam locomotives moving in reverse and only those steamers with 8 or 10 driver wheels. The cause of the derailments seems to be the trailing trucks which are very “springy”. The site of the derailments is actually where the first turnout on the ladder connects to the turnout leading into the yard ladder off the mainline.
Although that first turnout on the ladder sits on cork, just like the mainline, it is slightly sloped toward the grade. I am considering replacing that first yard ladder turnout with a section of straight track, bypassing the first yard track adjacent to the mainline. I would connect that replaced turnout on the second yard track to reconnect to the first yard track.
Hope that all makes sense.
Rich
By the way, none of my steam locomotives have any problems traversing the entire yard ladder when exiting the yard moving forward.
Rich
I have a smallish HO layout. Accordingly. I chose to make the Homabed roadbed shallow-1/8" thick-so it does not appear too dominant. Yards, sidings and spurs are on the flat, below the higher mains. Tapered transitions connect them to the mains. Turnouts are level, the transitions begin at the ends of the turnouts. It all works well. I have seen at shows some turnouts that are on a slope; the club member said that was not a problem as long as the turnout was level across the track.
Dante
So, all of the turnouts on the ladder were level and at the same height as the mainline track?
Rich
They are level either at or below the main line track.
Just build up the area under your yard ladder with the same thickness as your roadbed. Then you won’t have any grades and the yard track will be at ground level.
For example, if you use 1/4" cork roadbed on the mainline, you can put sheets of 1/4" cork under your yard tracks to bring the top of the rails up to the same height as the mainline.
Matt
On a layout for a club I used to belong to, the several mainline sidings were built lower than the main. The grade change happened right at the switch. IN it, really. Derailments galore.
We went through all those sidings and moved the grade transition from the switch, past the corrective curve, and into the straight part of the siding. It was fun. We broke out the ballast, jacked up the track, and re-applied more ballast. Kinda like the big guys do.
Derailments on those siding vanished.
These were passing sidings, not yard tracks. There was plenty of track room to do the trick, something not always available in a (model) yard.
Nevertheless, it demonstrated that it is better not to have grade transitions in a switch.
The problem is much worse for us than the prototype. Note that there’s another topic extolling the use of equalized trucks. Like the real ones. Note also that most of us don’t USE equalized trucks. And then consider steam locomotives.
So what could/would work on the prototype may not work for us. And, by the way, it can go in the other direction for other problems.
Ed
Not trying to start a battle here, but that indicates a problem with the way the transitions were built, or with the track laid on top of them.
That is certainly one way to fix the problem, but it’s much more common for the elevation transition to begin in the curve immediately after the switch than it is to maintain the mainline elevation past the curve (at least from what I’ve observed all over the country in the past 45 or so years).
Doesn’t matter. Where passing sidings are on a lower elevation, the transition generally starts right after the switch, in the curve. Of course, not all passing sidings drop to a lower elevation.
Sorry, but here I have to disagree. What it demonstrated was a flaw in the trackwork. Offhand I’d guess the transition was too abrupt (ramp too short, or not eased into and out of).
I’m sure you’re right about that. We don’t have equipment riding on partially compressed springs, so even a fully sprung and equalized model suspension - loco or rolling stock - is much stiffer, relatively speaking, than the prototype.
I do, because that’s all the motive power I run (
Mark,
Clearly, whatever the guys did originally didn’t work, or there wouldn’t have been the observed derailments. Our belief of having the vertical curve moved down to the straight section seems to have worked out, since the problem went away.
There may have been other ways to have handled the problem. We could have kept the same concept of starting the vertical curve just after the frog, but been MUCH more conservative in grade change. That appears to be what you prefer.
However.
Our approach worked.
I do not recall the amount of drop for the passing sidings. Nor do I recall how fast the drop happened, either before or after.
It’s my belief that grade changes on straight track are safer than on curved track and/or switches. So, at least for mainline passing sidings, I will stay with that concept.
For steadily decreasing qualities of trackage, I likely would revisit this. I would surely be tempted to do some whoop-ti-doo in industrial trackage–it looks pretty neat. And occasional derailments on such trackage are prototypic.
Ed
Thanks, Matt. I like that idea a lot, and I am leaning toward doing just that.
Rich
That seems to be the majority opinion here, and it makes good sense to me. Thanks, Ed.
Rich
It also makes good sense with Union Pacific. Here’s what they said in their book “Engineering Track Maintenance Field Handbook”:
“The top-of-rail elevation of main and diverging tracks must be level with each other through the turnout, and, where possible, for 250 feet beyond the signal or fouling point, whichever distance is greater.”
This was our approach, though we didn’t go for the full 250 feet.
Ed