what is the best way to transition from mainline roadbed rail hieght into the switch yard? there needs to be some kind of transition to table top level. Or raise the entire yard to roadway level. how about a gentle cookie cutter slope to table top level. what’s to most accepted method?
There is no “best way” to make a yard transition. The real railroads did any number of things that worked for the particular location, and there are an equal number of model railroads that did the same. If you are modeling a specific prototype location then follow the pattern they used, othewise do whatever is easiest for you to accomplish the task. Nobody is going to know the difference and the only one you need to satisfy is yourself.
Any of the methods you mentioned will work just fine, and I’ve also seen the real railroads just use a sudden drop from mainline to yard, nothing fancy in track geometry or splicing, as the following photos show.
Wonderful pictures! [:D]
The big thing that the real RR try to achieve that it is best to copy is to keep the railheads level across the track. If this can’t be done the rail that will usually be higher is the one on the outside of the curve. There are examples of the opposite - sometimes caused by lack of maintenance or subsidence - but they are likely to be problem areas and movements will be extremely slow to try to avoid cars’ wheels climbing the rail and derailing.
In a similar vein it is preferable to avoid beginning the change of grade until as far beyond the common crossing (frog) of the switch as possible. Again there are examples of the grade changing even right in the switch… I would not try to model that.
The best plan is to keep things as geometrically simple as possible.
You don’t actually have to alter the level up or down in a model. Apart from the fact that real yards could remain at the same level as the main track you can achieve a visual illusion by changing the colour(s) of the ballast and surrounding ground.
Another thing to consider is that when main track is re-ballasted - which is a main cause of the increased height of main track - the RR normally work on the plain track seperately from switches. Switches are much more complicated for re-ballasting and ballast cleaning - even for just tamping. It is important to maintain the geometry of the switch.
When a switch is worked on the work doesn’t just affect the one track. If any change is made in the height (or any other orientation) of the switch this will require work on whatever it is connected to. This is more work and more down time.
Switches may have their level (or other factors) changed but it will show up in whatever they are connected to. this is likely to include an element of new/cleaned ballast for a distance in the diverging track. While the work is going on it may mean that the div
Good analysis Dave, but I would add from real world experience that it is nearly impossible to LOWER track to meet a geometry requirment. Lowering track usualy can only be done during an undercutting operation which is complex, slow and very expensive. A UNIMAT tamper such as an 08-16/3S makes short work of tamping a switch so that is no problem. For all practical purposes, track is always lifted to correct geometry errors and ballast added as required to fill any vacant cribs.
Tamping a switch is no problem, note from the photo the heads telescope out and the entire unit can swivel as well as allowing independent control of each head. Rollers or hooks can be used to clamp the track so there is no problem at all tamping through the frog and points.
So is it safe to say from what is gathered here that most likely two track sections that have a great difference in level now could have been a lot closer to the same level 60 years ago?
Meaning mainlines that appear much higher now that unused or little used sidings may not have been that way originally?
Thanks for all the info!
Yes, it is perfectly safe to say that. One track may have been used more than the other, or one is newer than the next so one might have more ballast underneath due to repairs over time. For the most part in order to get a good geometry correction and stable ballast tamp you have to lift the track a minimum of 2" (roughly the diameter of the ballast stone you are using) even on the tangent. In fact, in the begining yards were the same elevation as the mains, but over the years the mains got repaired, the yards (and sidings) didn’t, so on some tracks I’ve seen the yards can be quite a bit lower than the mainlines and normaly the only time the yard lead gets tamped is when the mainline switch is repaired or tamped or there is a new piece of equipment they want to test so they use the yard lead for experiments (it’s a way to get a “free” tamp or tie replacement of the yard lead). So figuring very roughly a 2" lift about every 5 to 10 years on the mains, minus a bit for settling over time, in 60 years you could have 12-24" of elevation added. This is particularly worrysome where catenary is involved, but that is a different animal all the way around.
Remember when it comes to track repair the railroads are cheap, I don’t mean “thrifty” I mean CHEAP with a capital C. Since yards are for storage of equipment, sorting of trains etc, and all of it is a speeds of less than 10mph, the quality of track is not very important and it can deteriorate quite a lot before it needs something done to it. I’ve tested tampers in some yards that I won’t name (but will remain BNSF) that were so bad when you tried to lift the track it pulled the rails off the ties. The yard tracks start at the last long tie of the divergent route of the switch, at that point the track can change very suddenly from nice to junk depending on the age of the yard.
So with all that said, unless you are modeling a particular place on a particular prot
Hi!
Your question is timely as I just finished doing what you described on my HO layout.
The mainlines are on the standard 1/4 inch roadbed. As I did not want the yard to be on the tabletop plywood, I glued on a 3/32 (standard thickness from Office Depot cork rolls) as a base for the yard tracks. I then decided to add a second layer, which left me about 1/16th of an inch from being level with the mainline tracks. I took some cardstock and made a layered bevel for the remaining transition.
While it sounds like it would look “funny” with it all on the same level, it really doesn’t. The key is to keep about a 1/2 inch space between the roadbed and the sheet cork - kind of like a drainage ditch.
By the way, the main reason I did this is that those grade transformations with (in my case) curves and turnouts involved, often give trouble down the road. I’ve been there on the previous layout, and wanted to avoid it on this one. I did, and it works.
" …it is nearly impossible to LOWER track to meet a geometry requirment. "
No it isn’t [:-,] it’s just exhorbitantly expensive! , Which I’m sure that you will agree is why they make very certain that they get the geometry right approaching anything like a tunnel where the clearances are tight. On the other hand I have known a lot of cases where they have opted to raise bridges as the far cheaper option… mainly when installling overhead cables.
I don’t think that I actually meant an option of lowering (???) What I meant was that, rather than have to do a lot of messing about they are quite likely to keep a switch or other “fixed feature” where it is and make a slope down into and up from it to the new level in the plain track on either side.
Certainly modern tampers can do “wonders” (so long as the computerisation doesn’t get messed up) but this has only been the case relatively recently. In particular track maintained by lots of shovels was a different world. (In some ways it was better - so long as it wasn’t you pushing the shovel all day/night).
Hope this clarifies.
[8D]
oops! posted twice…
WHERE’S THE DELETE OPTION GONE?
[8D]
Yes, you are quite correct. Ramping in and out of a fixed feature such as a bridge or road crossing is quite common. The idea is to build such a feature higher than the trackage so over time the rest of the line will rise to meet it. I’ve not seen it done much with a switch, since as you say modern tampers can do wonders with them and it’s no big deal anymore to tamp right through them. The only difficulties I’ve encountered were at interlockings like Bridesburg station in Philly where some new construction was put in where the rails were cut too long and by lifting one switch it pulled the opposite switch out of line- but thanks to the modern miracle of AGGS the defect was quickly found and corrected.
And for the old days of shovels and track bars- well, it paid the bills and built character [(-D]
One reason that sidings and yards are at a lower level from the main line is to reduce the possibility of a car rolling from the siding/yard on to the main line.
I saw a hopper get away from the yard crew at the power plant coal dump at a shipyard I worked at many years ago.[:O] I was surprised at how quickley the car picked up speed. The crew would spot the cars with wood wedges blocking the wheels, and with the brake off. When it was time to move the car, they would remove the wedges and roll it onto the coal dump. When it took off, one guy [C):-)] jumped on the car and put on the brakes using the handwheel. He was followed by one of the shipyard’s Brownhoist cranes blowing it’s whistle to warn people that something was coming fast.
On my HO scale layout, I use cork roadbed for the mainline which is 1/4" and 1/8" sheet cork cut to roadbed width for the siding. I transition from mainline to siding by running the cork roadbed for 4 or 5 inches beyond the beginning of the transition and shave it into a ramp with a Surform block plane file.
I just lower my cork into the foam. I find it much quicker and easier to do than grinding down the cork. Any errant gouges are quickly filled by the caulk. I find it easier to get a nice transition that’s more even as the surface of the cork does not change. Sometimes when grinding down the cork I would end up with some dips and bumps. But not with this method. If you have plywood for a base you can use a chisel and mallet to do the same thing.
Brent
Hmmmmm [^o)]
I’m not going to say that building a yard lower than the Main will not stop a runaway from getting out… but (If it were my RR) I would like it to be a lot lower to achieve that. It is surprising how much speed a car can pick up in a short distance. Clearly a loaded car will get going better on a down grade… but an empty (even on a slight upgrade) with a good puff of wind behind it or, better still, at just the right angle for it to “tack” like a sailboat… well then you have an interesting situation. A couple of feet would probably not do much to hold back a boxcar or anything similar that the wind could get hold of.
I have known one or two instances of cars “getting away”. They have usually escaped on down grades but, given the chance to get up a bit of speed they will go a long way up a following adverse grade… until eventually they will come to a stand (provided they don’t go over a top and start down the next down grade)… however, once they have stopped on an upgrade they will come back… gathering speed as they do. So long as they aren’t going to hit anything the best thing to do is to let them sort themselves out. This “upsets” management but if they want to try a flying tackle with several tons of moving metal they are welcome to.
The best thing to do with any runaway car is to drop it in the dirt… or a sand drag if you are somewhere “posh”. Derails do their job but tend to damage a car more than letting the planet stop it.
One thing to model inline with a drop-off is the flange marks in the ties(if they are wood). you can kick the ballast back into place but you can’t get rid of deep dents in ties. (Not that I’ve ever… [:-^] ) (Concrete ties “chip” on the approach side(s) if the ballast is lower than the tie top and/or not firmly compacted around the tie). (That becomes approach side
Something else I intended to mention… If you have a track still in use next to dead track it may not only be at a higher level but it may get re-aligned to a better curve… this may cut into the “territory” of the out-of-use line. It’s a detail but it’s one of those things that can be used to add “history” to a scene.
Dead tracks are just dead tracks but a re-alignment shows that new money has been invested to improve the working track… and, potentially, to permit a higher line speed.
A re-alignment is quite a big job - even over a short length of track. A RR will tend to prepare as much of the site as possible without affecting traffic before taking a few days - if possible only a weekend - to rip out the old track/alignment and install the new.
I was on a job where an office person (read “complete idiot”) had planned to shove about 250 yards of track sideways into the position of a new curve using bulldozers. Shall we be polite and say that “this was not going to happen”. Even if the ballast had been shovelled out from between the ties there was too much weight/friction/mass etc in the track that had been in place for at least ten years. Track is designed to stay in place sideways as well as lengthways - and vertically. The comments of the engineer in charge on site were (shall we say) “quite colourful”… and then someone dug through a water main [(-D][(-D]
That reminds me of another thing…
Most track alignments will have some element of drainage aligned with them. this means that to change the track alignment you have to change the drains in the free ground first. and you will have to change any drains affected by the track you are moving between ripping out the old and starting to put in the new. all this will mean that there will be new drainage materials and works lined up ahead of the track being changed.
If there are any signal or power routes they may have to be changed as well.&
I do my transition a little different than has been mentioned so far. I have a yard that feeds into an industrial area and then out onto the mainline. My roadbed for the mainline is standard 1/4 inch cork. For the yard and industrial area, I laid out 1/4 inch sheet cork that I found online at a school supplies place. It comes in rolls that are 4’ wide and various lengths. So I really have no change in height. To make the transition less obvious, I have my mainline hit the sheet cork in a scenery break that is a wooded area.
You mean like this?
You mean like this?
EEEK!
That’s impressive! [tup]
Got any more please? [:-,]
[quote user=“tangerine-jack”]
You mean like this?
I most certainly do [:)] Although there looks to be little or no difference in height. Do you know if the two clean ballasted roads were done with a High Output Ballast Cleaner and the ballast topped up with an auto-ballaster set of hoppers? It looks very much like they were. Looking again it appears that the middle track has been completed by an HOBC while the far track has just had raised shoulders run in from a ballast train… the 4ft way is not just darker but the ballast is low to the tops of the ties.
Over on the right are the yellowed plants in a long line reeds or similar in a drainage dutch?
This is a superb shot for modern modellers.
You mean like this?
I most certainly do [:)] again. [:)]
But notice the way that the scissors crossover, while on a grade, is almost all on one plane… at least it was before it was allowed to get in a mess.
I think that the yellow box near the front is a switch motor… is it to drive the near switch blades or is that a derail just this side of the tip of the blade?
What is the mesh/grid there fo
I think the worst of the lot is CN rails, one side is jointed, the other continuous, then it switches for a while to all jointed, then it will flip to the other side will be continuous and all the ties are covered in moss- you can never figure out which side of your fillings are going to be knocked out next! A close second is the Bay Coast RR- 80 miles of 19 to 29ft jointed hell- makes you feel like a human pin ball ball at a blistering 10mph (with speed restrictions in certain places!)
Funny thing about the yard photo is that derailments are unheard of, but random uncouplings are common due to the sliding of the knuckles verticaly. The switch was lined as it was because they needed the frog to repair a switch on the main so they stole one out of the yard. In the real world you can have very bad track and still run a train, not so much in HO- if you had track like that in miniature nothing would run and it would be a simple static display. But, oh if I could only simulate the sounds that stuff makes in miniature!
For to answer the questions, the ballast was dropped by a new Herzog ballast train with laser measuring and computerized hopper distribution and such (yet to be made to work properly). The track at this time was wating to be tamped, but the multimillion dollar Herzog failed to drop ballast in the gauge.
Switch motor? Are you kidding me? It’s the 0-5-0 e-manuel ground throw, it’s yellow so you dont’ trip on it. The mesh and plywood is to keep you from falling into the water, that is the hinge point of the car float apron. What is far more terrifying than the track here is the fact that it leads to a car float that is just as well maintained as the yard, for a real thrill ride you should drive something onto the car float, through the yard (hold breath)- across the 4" gap in the apron (pucker factor x6) and onto a 480ft car float which last saw maintenance sometime around WWI with no wh
Which is basicaly what they did with 4449’s off pilot at Trainfest, she split the switch and they spent the good part of the night “shimming”. And, onece thye got her up, they backed and dropped her pilot again off.
One more on the height of yards. Like they’re saying, cars can speed up quite a bit, and no dip from one grade to anoither is going to stop a determined car under its own momentum. For example, Avon Yard sits on a bowl, with Indy to the east in the bottom of it. in the 90s, a string of cars got out of Avon, and foruntatley the tracks were cleared because they rolled ~20 miles into town, so far that a switcher from Hawthorne on the EAST side of Indianapolis was the closer engine to get them. And I think we remember the tragedy from a few years ago…