I am designing my first HO scale model railroad classification yard and would like to calculate the operating capacity of my yard.
Yard is approx 12 feet long and I have 2 A/D tracks that each hold 12 cars. Four classification tracks each hold 8-12 cars (see image above).
My thought is to run 10 car trains + locos and that's about as far as I've got....
Any thoughts on how to optimize for best results? I am open to any redesign ideas as (other than the mainline) no tracks are down yet.
Thanks!
Bernard
You could post a layout sketch and we can help more. Have you read 10 commandments of yard design? (Look up Houssotonic Railroad) Two quick things I would mention is you seem to have all body tracks double ended ... Single ended will increase capacity.
Second, I don't see a yard lead. Do you have one?
NP.
For the A/D track capacity, consider that you can always double a cut into or out of one of the other yard tracks and onot a cut in the A/D track easily enough, so you aren't strictly limited by the capacity of the A/D tracks only.
Mike Lehman
Urbana, IL
The design would depend on how the trains you're building fit into the rest of your operating plan. I'll give an example of my Junction City yard, pictured here:
This yard (starting from the backdrop) has the mainline, siding, seven classification tracks, and a thoroughfare. The "pass" (siding) can be used as just another yard track as needed.
Here's where I can insert my rant about design. The hobby press has done a disservice to modelers by suggesting small yards should have dedicated arrival/departure tracks. Very few such prototypes have them, and setting aside A/D tracks in a small yard decreases flexibility greatly. In my example above, the main and thoroughfare have dedicated functions, but the other tracks can be used as needed. Trains come and go from whichever track makes sense at the time, just like the equivalent prototype yard would have worked.
The yard functions around the blocks that need to move. Those required for Junction City are Union Pacific (eastbound to staging), D&RGW (also eastbound, but to another interchange connection in staging), Western Pacific westbounds (to be re-classified as needed further down the line i.e. staging), Lakeview shorts (cars to be worked out of the yard at Lakeview, which serves various industries), Milton Turn (a local serving the towns of Chester and Milton), and Raft River Turn (another local switching only its namesake town). That gives me six blocks for the seven class tracks, hopefully allowing at least one track in addition to the pass and thoroughfare to be available for other work as needed.
While some trains originate and terminate here, others only swap blocks. For example, an eastbound may pick up cars for the UP, dropping cars destined for local customers so the yard can classify them further. The locals pretty much just take whatever's on their tracks (and once they return the yard will classify the cars they bring back by destination so they can head east of west). One westbound that gets built here will take Lakeview and fill to 18 cars with WP.
The analogy I like to use is that a yard is a filing system. It's used to sort cars for efficient assembly into trains. A block is a group of cars headed to the same destination or otherwise kept together so trains can handle them effectively. As such, the yard should allow your crews to sort into the blocks they'll need and keep them discrete. In addition to the above, you'll need sufficient leads, crossovers and whatever to get trains in and out while keeping classification switching out of the way. If you can get hold of the articles in Model Railroad Planning (from Kalmbach) and maybe the Layout Design Special Interest Group (LDSIG) the design process should become easier.
Rob Spangler
NP01Single ended will increase capacity.
I'm with NP. Unless you intend to switch the classification tracks from both ends of the yard (in which case you'd want switch leads on both ends) the extra capacity is likely to be more useful than having the tracks double ended. Keep the A/D tracks double ended.
I have the right to remain silent. By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.
NP01 You could post a layout sketch and we can help more.
You could post a layout sketch and we can help more.
Working on that now but my plans keep changing...I mean evolving.
NP01 Have you read 10 commandments of yard design?
Have you read 10 commandments of yard design?
Yup!
NP01 Second, I don't see a yard lead. Do you have one?
Yes, it is labelled on the far right of the photo.
Now that I've had a chance to look more closely at your yard, I'll suggest a few things, assuming your design isn't attempting to copy any specific prototype track arrangements you need to maintain visually.
If necessary, separate ladders can be employed side-by-side to keep tracks from getting too short.
The yard I described in my earlier post has ladders at one end that look like this. This arrangement prevented the tracks farthest from the main from shrinking too much.
I'll back Rob's comment about A/D tracks. On the prototype they will be found in big hump yards but few are modelling that type of operation. Yards of the typical size and style found on model railroads do not have them. Instead the yardmaster (if there even is one) will try to have at least one yard track track clear of cars in advance of an arriving train. Often this will be close to the main track(s) simply because it is the longest track. It will also be a track connected at both ends but on the prototype that will be the usual form for all the body tracks.
Single ended yard body tracks can be found, but are the exception. They are forced by geographical constraints, such as a lake, and usually the main line will also terminate. Tracks serving industries, team tracks, caboose tracks and the like are, of course, commonly single ended but those are not normally used for classifying cars.
A switching lead is useful, on both the prototype and model, since switching moves don't get interrupted by trains passing on the main line. But they are only a "nice to have", and often the prototype did not see enough value to actually spend the money to build one. Simply use the main line, clearing back into the yard for through trains. DCC makes that operation much easier than the older block power control systems.
John
wp8thsub Now that I've had a chance to look more closely at your yard, I'll suggest a few things, assuming your design isn't attempting to copy any specific prototype track arrangements you need to maintain visually.
Thanks for the suggestions. The yard isn't based on anything other than the desire to base it on the principles of good model railroading.
wp8thsub Eliminate the separate runaround at right and have the ladder come off the same track. That will provide extra capacity for the body tracks, and keeping turnouts off that track doesn't appear to provide an operational gain.
Eliminate the separate runaround at right and have the ladder come off the same track. That will provide extra capacity for the body tracks, and keeping turnouts off that track doesn't appear to provide an operational gain.
I thought, based on what Ive read that the separate runaround at right was essential to allow road engines to move unimpeded to the service area while the switcher works uninterupted on the yard lead????
wp8thsub The yard I described in my earlier post has ladders at one end that look like this. This arrangement prevented the tracks farthest from the main from shrinking too much.
I'd love to see the track arrangement just to the left of this photo to see how it all comes together! Thanks for the comments.
trafficdesignI thought, based on what Ive read that the separate runaround at right was essential to allow road engines to move unimpeded to the service area while the switcher works uninterupted on the yard lead????
You do need access to the service tracks, but the switcher will still block access to the lead as it works the ladder in your plan. The only thing you're gaining right now is an extra few feet for a loco to move to the right before the switcher blocks it. Just about any time the switcher is working the ladder, it will foul the access to the track labeled as "runaround." It will have to work across the turnout to the runaround unless it pulls into the lead or up the ladder. The runaround/thoroughfare still functions the same in your yard regardless of whether it's a few feet longer.
Again, beware yard design commandments in the hobby press. Sometimes they stress "must have" design features that prototype yards rarely have outside major terminals.
trafficdesignI'd love to see the track arrangement just to the left of this photo to see how it all comes together!
Here it is before ballast and weathering. The two ladders tie into the siding and then you have a crossover to reach the main. The photo of the finished trackwork shows the turnout added later to reach a track for company materials and sand that I installed behind the diesel shop.
I have a setup for my freight yard very similar to the one contemplated by the OP.
My yard has crosssovers from a double mainline at both ends of the yard. The first track adjacent to the inner mainline track is the A/D track, extended at both ends to form lead (drill) tracks. The classification tracks are all double ended, and the last "classification" track is the switcher runaround track.
The recurring suggestion in this thread is to drop the A/D track idea. But, I have always understood the A/D track to be appropriate, if not essential, to good yard operation.
An arriving train uses the A/D track to drop off its cars, so that the road loco(s) can then head for servicing. A switcher eventually arrives to remove the cars to the classification yard and the caboose to the caboose storage track.
Once a departing train is assembled on the classification tracks, it is moved by the switcher to the A/D track and then the road loco(s) arrive to remove the assembled freight cars to the mainline.
Rich
Alton Junction
Many prototype yards would just have the shifter drop into the clear for a minute to let the road power get by. Or, better yet, let them drop into the clear and take a break.
richhotrainThe recurring suggestion in this thread is to drop the A/D track idea. But, I have always understood the A/D track to be appropriate, if not essential, to good yard operation.
A lot of prototype yards functioned very well without dedicated A/D tracks.
Unfortunately the OP is not building a full size yard. He only has 12 feet to work with. It has been proven many times over the years that the yards in model railroads with a modest amount of space work well with a mixture of double and single ended tracks. The amount of traffic that can be accommodated on these size layouts can be adequately served with just a couple double ended tracks. John Armstrong wrote about this repeatedly.
While they don't necessarily need be called or dedicated A/D tracks, it is a convenient name to use for the double ended tracks.
The hobby has relentlessly pushed this idea for 30 years, partially in design articles, and then from the misinformation in those articles filtering through discussion forums and elsewhere. Yards small enough for inclusion on most of our layouts, even including club situations, almost never had anything resembling dedicated arrival/departure tracks. None of the prototype yards where I've railfanned in my area have them, including the division points. They're certainly a feature of hump yards, where trains aren't going to move across the hump to do work. How many of us model those? Despite the lack of support from prototype yard functions, the idea has become sufficiently ingrained among some design afficionados that it's taken virtually as a commandment. Unfortunately some of the people engaged in that groupthink have written influential articles.
In model situations, the removal of flexibility from taking tracks out of service from the main body of the yard can make it WORSE. I've seen model yards that got unnecessarily plugged for want of an extra body track at times, but where the owner stubbornly insisted on keeping the A/D tracks free for arrivals and departures only.
An arriving train uses the A/D track to drop off its cars, so that the road loco(s) can then head for servicing. A switcher eventually arrives to remove the cars to the classification yard and the caboose to the caboose storage track. Once a departing train is assembled on the classification tracks, it is moved by the switcher to the A/D track and then the road loco(s) arrive to remove the assembled freight cars to the mainline.
The operating scenario thus described is common on model railroads, but not really so on the prototype.
The train will arrive on whatever track is designated by the yardmaster (assuming there is one). Road power will be cut off and moved, then the yard crew goes to work breaking down the train to the other tracks, and putting the caboose away.
When a train is ready to depart, it will be assembled wherever is needed. Oftentimes this will consist of the road power and caboose being tied onto a block already existing in the yard somewhere, or they will double two or more blocks before pumping air and performing the required departure inspection. Sometimes the process of combining blocks is done by the yard switcher, other times the road power will do it. The latter may be done by the road crew or yard hostler depending on local union agreements.
Pulling cuts out of the class tracks, and moving them to A/D tracks, can slow operation in a smaller yard. Big terminals have arrangments of runarounds, escape tracks, separate leads, and so on that facilitate these moves.
Bernard:
From your orginal post it appears that you are using simple ladders.
Have you thought of using a compound ladder to increase siding capacity.
The other question is single operator or multiple. For single operator, using sequential operations, any yard will work.
This is mentioned in some track planning books.
David
The opposition to an A/D track seems too severe. The OP would like to include an A/D track, so why not? As a lone wolf operator, I find the A/D track to be fun and prototypical.
I pull a train onto the A/D track, uncouple the loco(s) and head for the servicing facility, steam or diesel. The cars on the A/D track sit there until I find time to send a switcher to move them to the classification yard.
Besides, was that common practice to send road engines, particularly consists, through the classification yard tracks? I thought that yard switchers mainly did that.
richhotrainThe opposition to an A/D track seems too severe. The OP would like to include an A/D track, so why not?
My opposition to it addresses two things that could affect the OP:
If the above are based on attempting to replicate yard functions that wouldn't normally exist, why design a yard around them? If somebody wants such features in a design, no harm done, but if he's doing it because of articles and such that are peddling bad information, it may increase enjoyment in the long run if they're avoided.
richhotrainBesides, was that common practice to send road engines, particularly consists, through the classification yard tracks? I thought that yard switchers mainly did that.
That was, and is, EXTREMELY common.
Here's a WP local pulling into the yard in Salt Lake City. Note that it's heading into one of the body tracks that happened to be open. Power will cut off from there.
This aerial view is of the same yard many years later. Note the presence of road power in the body tracks.
http://www.wplives.com/diagrams/yards/YD024.html
http://www.wplives.com/diagrams/yards/YD028.html
The links above are to track diagrams of WP division point yards at Oroville and Portola, CA. Trains came and went from whatever track, and road power of necessity used the ladders and class tracks. These are typical of many roads' yards.
Well, then, I guess that the next logical question is, why have an A/D track at all?
Is it wasted track for railroads that do have an A/D track?
richhotrain Well, then, I guess that the next logical question is, why have an A/D track at all? Is it wasted track for railroads that do have an A/D track?
When the prototype sets these up, they're typically in very large termianls with distributed yard functions. When enough real estate can be devoted to separating different work within the terminal, yards can be split.
Here's an example of a prototype with separate receiving and departure facilities, the UP hump yard at North Platte, NE. Bailey Yard is gigantic, allowing functions to be separated efficiently. Note the networks of leads and crossovers between a receiving yard, hump, class tracks, and the corresponding departure yard. There's enough space to keep all the independent movements out of each other's way, and no concern that tracks will end up too short for the required capacity. Only in very unusual circumstances could a model yard be able to replicate this sort of thing.
We may be making too big a deal here of what are esssentially labels. Since most of our layouts are constrained by size, the main thing that's needed with the function of an A/D track is simply a track with easy access to the main that is either long enough in itself or is adjacent to tracks where one or more cuts from them can be added before departure or, similarly, to do the reverse.
The narrowgauge rarely had any fancy facilities, but we know they used certain tracks to build and tear down trains as most were too long to fit in the yard proper. My Durango is similarly limited with a yard with just 5 tracks (plus a short storage stub). The two longest ones are usually used for A/D, in part because there's a crossover midway along. a 6th track in front of the station can serve as a through track in a pinch, but don't dare park any freight on it. There's also a siding at Carbon Junction where I can park cuts or whole trains until ready to go.
Most longer trains are doubled out. Arrival can vary, depending on what' in the train, but whatever is done, get it broken down and out of the way ASAP.
Thus my yard tracks can serve any purpose and often do. It's just that the longest ones are naturally favored for A/D purposes.
davidmurray From your orginal post it appears that you are using simple ladders. Have you thought of using a compound ladder to increase siding capacity.
Thanks David. Would love to, but can't seem to wrap my head around how to do this? Anyone have a bulletproof (idiotproof) compound ladder trackplan they can point me to?
davidmurray The other question is single operator or multiple. For single operator, using sequential operations, any yard will work.
Initially myself plus kids (aged 9 and 7) but would love to design something than can grow as my knowledge of operations gets more advanced.
trafficdesign Thanks David. Would love to, but can't seem to wrap my head around how to do this? Anyone have a bulletproof (idiotproof) compound ladder trackplan they can point me to?
This is a compound ladder. It's small but I'm limited by space. I can fit 2 or 3 more cars in the yard using the compound ladder than if i used a "conventional" type ladder. My 9 year old nephew figured it out within a few minutes. Bulletproof/idiotproof? Not sure.
T e d
Is this a compound ladder? Did I get it right? Wondering if this track arrangement will work?
Yep, that's it. Basically, instead of having a single lead, a compound ladder has multiple leads that branch to take as little space as possible.
My Durango yard employs compound ladders. It's a distant shot, but show how things started out.
trafficdesign
I'm not up to speed on yard ladder terminology, but I think your plan can be done a little neater:
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
I'll agree with what Rob and some others have posted. For a yard that size, you don't need a dedicated Arrival/Departure subyard, only some double-ended tracks to allow trains to arrive and depart. Keeping these tracks as part of the rest of the yard allows operators to "swing" tracks from one purpose to another during a session, which can be handy in the model environment.
But since we don’t know what the rest of your layout looks like or how the yard will be used, it’s really not possible to say for sure what your yard should look like beyond that.
In my experience operating at layouts of various sizes, a dedicated A/D subyard seems to become helpful at around 10-12 yard tracks total, but again, it depends very much on how the yard will be used, the traffic flows and patterns of the overall layout, etc.
If you are interested in the yard capacity (as the title of the thread suggests), again, a lot depends on how you will use the yard. If you want to actively classify cars, build and terminate trains, etc., then it is best if you plan to only fill the yard to about 50% of its total capacity. If you are instead planning to just store full trains there, then the yard is more like staging and you can use more of the capacity.
Best of luck.
Layout Design GalleryLayout Design Special Interest Group
hon30critter trafficdesign I'm not up to speed on yard ladder terminology, but I think your plan can be done a little neater: Dave
I like it! Thanks Dave. It is neater and I like the fact that the thru track has less turnouts. I am using peco #6s any idea of what you used in the software?
I'm using Peco Code 100 medium turnouts. They are slightly shorter than the Code 83s but I don't think that will affect the yard ladder design.
Dave, what software was used to produce that diagram?