Grade in a Yard

[ericboone]

I am designing a basement sized multi-deck layout. I plan on having the layout gradually climb as it goes around the room to avoid having a helix. One level will have a long yard. The question is, do I keep the yard flat and have a 1.00% grade on the rest of the mainline to get the seperation necessary for multiple decks or do I put the yard on a grade and thus reduce the grade to 0.75%? I would like to run 40 car trains with one steam locomotive and am concerned that too much of a grade will prevent me from doing so. (I am modeling the Pere Marquette in 1946 and the PM only had a few diesel switchers and some E7s for passenger trains at the time.) Of course, if the 0.75% grade in the yard causes cars to start rolling on their own, I'll be very unhappy and have a lot of work to fix the problem. Has anyone had problems with cars rolling away from them on 0.75% and 1.00% grades? Thanks in advance.

[Anonymous]

Tuned rolling stock will find low spots that you didn't think existed. Even in a 'flat yard'. I'd keep the grade out of the yard unless you can think of a way of putting in retarders for hump yard operations.

[mcouvillion]

I agree with mstein. You are asking for trouble with a yard on a grade.

Mark C.

[rrinker]

No question, cars WILL roll on a .75% grade. Keep the yard flat. A 1% grade really isn't that much for a model. Gravity and friction don't scale, so a model train can pull better on say a 3% grade than the real thing can on a 1% grade. Best thing to do is mock it up and test it - bet you'll be suprised at how many cars you engines can pull on a 1% grade. You can always doublehead - 40 cars might seem short for the prototype to doublehead, but since everything else is condensed on the model, it really doesn't look out of place - unless you are building your layout in a hanger.

--Randy

[Anonymous]

I agree with other posters: You will rue the day you decided to put a grade in the yard. I think you may not be able to get a single loco to pull 40 cars up a 1% grade. A forty car train in HO is at least 21 feet long. MY question is, do you have room for 20 foot trains on your layout? Maybe some selective compression is in order here.

Your layout must be huge. A one percent grade will take 100 feet of mainline to climb one foot. How long is your run??? I wrestled with these issues and ended up making the deal with the devil and putting in a helix. My room is fairly small (13' x 22'), so I didn't have a lot of options. Sounds like you have more space.

Guy

[ericboone]

I think the outcome is unanimous. (I'm not suprised, but I thought I would ask.) Flat yard and a 1% grade on the rest.

The layout will fill the entire basement with the exception of a utility / work room. One level of the layout will have about 180 feet of mainline. Taking out about 40 feet for the yard, that leaves me 140 feet to climb 16 inches. This is a 1% grade.

I intentionally designed the layout to mimic the prototype with 6 to 1 compression of the mainline length. Instead of an uncompressed 60 feet per real mile, I'll have 10. (If you haven't guessed by now, this is an HO scale layout. [:)] ) This still allows for a nice distance between towns and long sidings for longer trains.

Thanks everyone! [:D]

[egmurphy]

Just think what you could do with N scale in all that space!! [:D]



Ed

[Anonymous]

If you have room for a loop (yes i said loop not helix) that can get your trains about 6 inches up without going anywhere.
hope this helps
~Brian~

[johncolley]

Note Tehachapi (any climbing) Loop going over itself is a 1 turn helix...duh! You should easily be able to handle 2 to 2 1/2% grades which will allow you to ease into them at the bottom and out of them at the top. If you've got the room there is nothing wrong with a helix to give you more mainline on the two levels. Also look into mushroom layouts.

[Anonymous]

A suggestion, and what I'm doing with my own yard:

The mainline is on a fairly constant gradient, and the yard ladder itself along with the first few (real) feet of yard track is on approximately the same grade. Beyond this point, the yard will flatten out, with the mainline continuing to drop; this is only possible on a stub-ended yard, note. The gradient separation between main and yard adds some visual interest, and the drop into the yard helps with switching, as backing long cuts of cars into the yard tracks is aided by gravity; I've been told that this will reduce derailments going through the turnouts. It's a bit like a mini-hump yard in this respect.

Personally, I find the accomodation of terrain one of the most intersting aspects of layout design, and the primary reason why I model the Appalachians. But, a flat yard might be much more appropriate given the geography you're trying to represent, and if you're needing a double-ended yard that will have an effect as well.

[Anonymous]

Keeping the grade out of the yard tracks is good . I like the above idea of the maniline continuing on a grade. Remember short grades even though steeper do not effect train performance if all the trains weight isn't on the grade at once. Perhaps, you could use short steeper grades at each end of the yard to catch up with mainline elevation. Possible to keep a double ended yard. A 4-8-4 steamer from LL or BLI with traction tires should handle 40 cars on a 1 percent grade. Maybe read a performanceb review on the Berkshire or similar loco.