So I'm planning to add a yard to my future HO layout and am looking for some practical advise on how to deal with a situation. My yard needs to have a 90 degree bend in it somewhere.
On the proposed benchwork I don't have enough length to get straight tracks and ladders all the way through. So I'm trying to determine where the bend should be. I'm thinking near the middle since the ends are where the turnouts which seems to be the area where derailments and coupling would be most likely. I can use a 36-42" minimum radiusat the aisle up to a 60" maximum radius.at the backdrop.
An alternative though undesireable is to shift the yard even farther down the mainline and make it U shaped. I could keep the ladders straight and the center straight or build it all as one large curve but it starts to throw off the balance of switching to mainline running
Modeling the Cleveland and Pittsburgh during the PennCentral era starting on the Cleveland lakefront and ending in Mingo junction
A working (versus passive staging) yard on a 90 degree bend is a considerable challenge. On my layout I have double track mainline, and at one corner the curves are 40" and 38" -- at two other corners the curves are 42" and 40."
The trains run nicely on those large curves but even with such generous curves, reliable coupling is not assured every time, and uncoupling sometimes involves more jabbing at the Kadee knuckle with a pick than is probably good for the coupler. Let's imagine I want a 6 track yard with 2 inch centers I could go to 44" for an outer curve and surely could get a tighter radius down to 36 or 34. But as a practical matter, that portion of the track on the curve becomes in essence "passive" -- it will hold cars fine but I am not sure I could actually "work" the part of the yard on such curves.
Curved yards can work, both in the prototype and on model railroads (Tony Koester had one on his old layout) but curved to 90 degrees seems to be a whole 'nother matter.
In short I think the central issue will be, where on this yard do you actually expect to be coupling and uncoupling cars and locomotives? I think necessity will dictate that it NOT be on the 90 degree curve except perhaps on the very outer track with the widest radius - which is an odd way to run a yard.
Dave Nelson
All things being equal, I would put the curve near the throat and use a pinwheel ladder. It saves space anyway and if you have to put it on turn, you can limit the area not usable. I'm stealling Stein's picture of one. I hope he doesn't mind.
Chip
Building the Rock Ridge Railroad with the slowest construction crew west of the Pecos.
A benchwork "inner-corner triangle" can be a way to allow for a broader curve radius at that 90-degree yard location. For example, make the 45-degree triangle with two equal 12" sides, or 18" sides.
P.S.: ...like the idea SpaceMouse!
Conemaugh Road & Traction circa 1956
SpaceMouse All things being equal, I would put the curve near the throat and use a pinwheel ladder.
All things being equal, I would put the curve near the throat and use a pinwheel ladder.
Respectfully disagree. Pinwheel ladders are fine and I use them in designs fairly often (especially in staging), but since the OP's concerns are automatic coupling at the yard track clearance points, a pinwheel ladder with curved body tracks as you've shown exacerbates the issue. [Edit: Of course, the example shown is not actually a pinwheel ladder at all, see my later post below.]
Better a curve in the middle of the yard and straighter tracks through the coupling/uncoupling points if addressing the original issue.
Byron
Layout Design GalleryLayout Design Special Interest Group
Ah, the pinwheel ladder. I was intrigued by this concept when I saw it in MR recently. I have the same challenge / opportunity as Rude Runner: expanding my too short (13 foot, with ladders) double ended HO yard will require going around a 90 degree inside corner. My thought was to take one ladder around the corner, allowing a few more feet for relatively straight yard tracks. I am not to the skill level to hand lay turnouts, however.
Which leads to my question: Can anyone provide plans & guidance for constructing a pinwheel ladder with commercial turnouts? Data and pics welcome, obviously, along with pros and cons.
For frame of reference, this is my first layout, HO around the walls of a 13' x 24' room, using 1x4 framing topped by 3/4 ply and 1" foam board. Atlas flex and turnouts, although I'm interested in upgrading. Pretty basic. I'm actually looking forward to a major tear up & rebuild this fall!
Thanks, Bill
onebiglizardWhich leads to my question: Can anyone provide plans & guidance for constructing a pinwheel ladder with commercial turnouts? Data and pics welcome, obviously, along with pros and cons.
Pretty simple. Each successive turnout springs from the diverging leg of the turnout before. You can also add a bit of curved track between each turnout to make the overall curve of the ladder sharper.
If you choose to add the curved track, it's best to choose a reasonably broad radius. I like to use a radius a little broader than what's called the "Radius of the Closure Rail" for the turnout. This varies with the frog number of the turnout, from about 22" in HO for an Atlas #4 (which is really a #4 1/2) to 26" for a #5 to 43" for a number 6, and so on.
You can build a pinwheel ladder with nearly all turnouts -- no need to handlay.
The pro is probably obvious: curved ladder, which may fit a particular space more easily and/or make the yard a little longer. The con has been mentioned: if you curve the yard body tracks out of the pinwheel ladder, it can cause problems for automatic coupling/uncoupling unless the radius is very broad, which works against the space savings somewhat.
Pinwheel ladders exist on real-life railroads, but are quite a bit less common than the standard "simple" or "straight" ladder, so some may find them slightly less realistic in appearance for that reason. As Andy Sperandeo mentioned in the article in the June MR, pinwheel ladders are more realistic than compound ladders (if you are modeling a hand-thrown yard in real life) because the switchstands are still all along one rail and the crew members on the ground wouldn't need to cross tracks.
Andy Sperandeo provides a more detailed explanation of building pinwheel and other ladder types in the Kalmbach book The Model Railroader's Guide to Freight Yards.
[By the way, the example shown earlier in the thread is a bit misleading, since it is not a pinwheel ladder. It's actually a simple straight ladder made of curved turnouts (no kidding), which has different pluses and minuses.]
cuyama Pretty simple. Each successive turnout springs from the diverging leg of the turnout before. You can also add a bit of curved track between each turnout to make the overall curve of the ladder sharper. <snip> [By the way, the example shown earlier in the thread is a bit misleading, since it is not a pinwheel ladder. It's actually a simple straight ladder made of curved turnouts (no kidding), which has different pluses and minuses.]
<snip>
Oops - my mistake. Here is a sketch of what Byron describes (unless I misunderstood him) - ie putting straight turnouts (in this case Peco code 75 medium turnouts) on the diverging leg of the preceeding turnout:
Smile,Stein
steinjr Here is a sketch of what Byron describes (unless I misunderstood him) - ie putting straight turnouts (in this case Peco code 75 medium turnouts) on the diverging leg of the preceeding turnout:
Here is a sketch of what Byron describes (unless I misunderstood him) - ie putting straight turnouts (in this case Peco code 75 medium turnouts) on the diverging leg of the preceeding turnout:
Quite right, that's a pinwheel ladder. Creates a curved ladder from "straight" turnouts.
I'll be danged. That's what I get for being hasty. My apologies to everyone I mislead.
Cayuma hit the nail on the head. My concern is where the curve is compared to where the coupling/uncoupling happens.
Having never had a real workin yard on any of my layouts before I'm not terribly sure where most of the activity will happen. So for those of you who have had functoning yards where does the majority of the coupling happen? Near the ladders as I suspect or towards the center?
FWIW I have a 24" shelf to work with but will need to fit a double main against the backdrop. I think this will allow 8 yard tracks maybe 10 but that would be a squeeze. Hoping to fit 14 ft yard tracks plus ladders on each end, depends on the length of the ladders.
ruderunnerSo for those of you who have had functoning yards where does the majority of the coupling happen? Near the ladders as I suspect or towards the center?
Mostly near the yard ladders, typically right at the clearance point from the adjacent yard tracks.
good read,but I have a question on the pinwheel ,does it create a problem for some 6 wheel truck diesels . seems I was playing with a configuration like the pinwheel and had derails on E6 p2k from having a curve into the points of a switch ( had to have a very small straite section before the atlas #6 ) if that make any since . just currios..Jerry
BIG JERR good read,but I have a question on the pinwheel ,does it create a problem for some 6 wheel truck diesels .
good read,but I have a question on the pinwheel ,does it create a problem for some 6 wheel truck diesels .
It shouldn't if the turnouts are broad enough -- maybe there was some other out-of-gauge or other issue at that point in your situation. If the curve is too tight leading into the turnout or the direction of the curve changes leading into the turnout, there might be an issue. But the diverging leg of a #6 feeding another #6 (diverging in the same direction) should be pretty accommodating, for example.
yep ,I think your right ,I went to my train room and looked @ the place where I had the issue .it was a left hand 22 curve going in to a left hand # 6 code 83 streamline atlas points set to the left turn possition e6s would climb the point 50% of the time ,stuck in a 11/2 " strait no problem....I checked the # 6 atlas turnouts and looks like the the turn straitens out after the frog so I would think it wouldnt be a problem in the pinwheel . Jerry
So sounds like keeping the ladders straight and putting the curve near the middle is the way to go. Question about the pinwheel setup though, does the curve formed affect cupling? can one run straight track for a distance from the frogs and then curve the tracks? Seems that may affect track spacing but may alleviate coupling problems.
The ideal for Kadee automatic coupling and magnetic uncoupling is both cars on straight track so there is no angle between them.
The more you deviate from the ideal the more likely you are to have problems uncoupling or coupling. Obviously, the smaller you can make the angle between the 2 couplers - curves with easements, broad radius, one car on an easement and the other on curve or straight, etc. - the less likely you are to have problems.
According to the LDSIG Radius Rule of Thumb (http://www.macrodyn.com/ldsig/wiki/index.php?title=Curve_radius_rule-of-thumb), you will have no problems with automatic coupling if your curve radius is at least 5 times the length of your longest car. In HO, that means for 40ft cars, a minimum 30" radius in the yard should work pretty well. And that tracks with other reports of curved yards I have heard of. Longer cars will of course need a bigger yard radius for coupling/uncoupling to work well.
my thoughts, your choices
Fred W
ruderunner Question about the pinwheel setup though, does the curve formed affect cupling?
Question about the pinwheel setup though, does the curve formed affect cupling?
Yes, curved body tracks in the yard create problems for automatic coupling. That's why I mentioned it specifically as an issue for you earlier in the thread.
cuyama Pinwheel ladders are fine and I use them in designs fairly often (especially in staging), but since the OP's concerns are automatic coupling at the yard track clearance points, a pinwheel ladder with curved body tracks <snip> exacerbates the issue. Better a curve in the middle of the yard and straighter tracks through the coupling/uncoupling points if addressing the original issue.
Pinwheel ladders are fine and I use them in designs fairly often (especially in staging), but since the OP's concerns are automatic coupling at the yard track clearance points, a pinwheel ladder with curved body tracks <snip> exacerbates the issue.
ruderunnercan one run straight track for a distance from the frogs and then curve the tracks?
That would be a pretty strange looking yard.
What benefit do you perceive that a pinwheel ladder would give you versus a straight ladder if you want the body tracks straight near the ladder and are putting the curve in the middle of the yard?
Cuyama (spelled right this time) I didn't percieve any advantage, just wonderd if there was an advantage other than allowing longer yard tracks. But I guess thats the tradeoff on a pinwheel ladder, longer yard tracks traded for coupling on curves.
Interesting tidbit about curve radii vs car length. Since I won't be running cars longer than 70' I should be able to couple in the yard except maybe closest to the aisle.
Time to start sketching this yard. Hopefully I can learn something from this before getting to the next yard.
played with the layout last night and made the pin wheel ladder useing #6 atlas custom line,important to note was you have to change the switch rod on these turnouts when in this configuration(stacking on the dev route)not a difficult fix once Ifigured out how to snap them out and reverse them. but was very satisfied with the results(the pin wheel ) ran some trains thru it and found to be very smooth,and I think it looks good ...(note here, my entire layout is just track and turnouts thumb tacked down to bench work but theres 60 pcs of flex and 20 turnouts ) It looks like the arch of the pin wheel is about a 60" radius ,any how Im happy with it for my small ish yard ,cant. wait to start putting things down permanent,but still in the testing the plan phase ....Jerry
Yards come in all sizes and shapes, both prototype and model. The available radius that you mention will give you a really nice yard. My main yard is 4' x 35' on a curve that is a little larger than what you describe, it is double ended and has compound ladders on both ends. I'm modeling an eastern railroad (the B&O) which was usually following a water level route. Linear yards were far and few between. Modeling derailments usually come from poor trackwork, long cars and tight radius curves. My minimum yard switch is a # 6, with several # 8's. A large curve would be more prototypical than having a bend at a particular location without a good reason. Think like the prototype! Your comment about having a large curve that will throw off your switching to mainline running needs a lot more explination to understand why.
ruderunnerFWIW I have a 24" shelf to work with but will need to fit a double main against the backdrop. I think this will allow 8 yard tracks maybe 10 but that would be a squeeze. Hoping to fit 14 ft yard tracks plus ladders on each end, depends on the length of the ladders.
Just a thought - maybe put in one or two fewer tracks to leave some room somewhere for dirt access road in the yard. As Paul Dolkos and others have pointed out, it makes the yard more realistic, which I think worthwhile even at the cost of fewer tracks.
- Dave
Cass are you referring to my hesitation to making a U shaped yard? Several reasons for avoiding that: 1 It would be at the end of an aisle,2 the maximum radius I can fit in that spot is 42" and that would be for the mainline, yard tracks would get down to an 18" radius, 3 it throws off the "scenic balance" for me. Meaning it becomes too far from the city and too close to the country.
But let me make sure I follow the curved yard idea: make the entire length of the yard tracks curve as opposed to keeping them fairly straight with 1 bend to make the turn?