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2% grade, 42" circle questions

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Posted by lionelsoni on Saturday, December 4, 2004 10:12 AM
I haven't done any experiment to confirm this, but it seems to me that longer cars would be more resistant to being pulled off a curve, since the trucks, being farther apart, would be cocked at a greater angle to the car body, making it harder to tilt the car. Longer, six-wheel trucks would also seem to give an advantage.

Bob Nelson

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Posted by Boyd on Saturday, December 4, 2004 1:52 AM
Sounds good. I like the longer, bigger cars, but I'm guessing with a 2% grade 10 long cars shouldn't be a problem. I possibly could do 15 or more. I can always add engines,, its the number of cars I can have in the train.

Modeling the "Fargo Area Rapid Transit" in O scale 3 rail.

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Posted by lionelsoni on Friday, December 3, 2004 10:22 AM
If the 42-inch loop is hidden, you might as well put some negative superelevation on it. That is, let the train lean a little to the outside of the curve to resist being pulled off to the inside.

Bob Nelson

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Posted by GPJ68 on Thursday, December 2, 2004 11:57 PM
I've got a 180 of roughly 42" old O guage track with banked ties on a 5% grade that my Williams WM Geep has no trouble at all pulling 11 new cars (mixed MTH, K-Line, and Ind. Rail), just needs a little more juice as it enters the turn. I'm purely guessing that the Williams should pull at least twice as many new cars up it, providing I don't hit any stringline problems. So far that turn is one of the few places I haven't had any derails yet, although it is a little unnerving seeing everything lean over into the turn because of the banked ties. 8 postwar dump cars put more of a strain on the Geep, but it will still pull them through, although it's gets uglier - think stringlining will start with a just few more postwar cars (already happening occasionally on some level O34 curves).

Not sure if that helps, but that's my experience to date.

As a side note, the pre-war 1666 will handle @ 6 new cars before its really chokes and starts spinning wildly. Maybe I need to add a working sand dome on it......
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Posted by Boyd on Wednesday, December 1, 2004 12:00 PM
Now that we are all on the same page, anyone got an idea how many newer cars I can pull up that loop with the 2% grade. 5, 10,15 or would I need pusher engines or would that be complicated with the 42" circle?

Modeling the "Fargo Area Rapid Transit" in O scale 3 rail.

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Posted by daan on Tuesday, November 30, 2004 1:44 AM
Now I understand your former post... Since we had this discussion going on about grades in a circle, I automaticly presumed you would want a spiral..
Daan. I'm Dutch, but only by country...
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Posted by Boyd on Tuesday, November 30, 2004 1:29 AM
The narrowest part of the closet is 45" so 042 would work giving extra space for overhang. If that is too tight then I would use some gargraves flex track I have sitting around.
The track going in/coming out of the closet would be next to each other only seperated by height, whatever a 2% grade would produce. It would be physically impossible to keep a 2% grade on a 42" circle and have the incoming/outgoing tracks above/below each other.

Modeling the "Fargo Area Rapid Transit" in O scale 3 rail.

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Posted by lionelsoni on Monday, November 29, 2004 9:56 AM
Boyd didn't say anything about a helix, just a loop.

If 42 inches is the actual width of the closet, O42 track won't work, since the diameter is a little more than that and you will need another half inch clearance from the wall for the overhang even on a tangent and an inch or two more on the curves. However, you may have already allowed for that.

If O42 won't fit, consider Marx O34 before going all the way to O31 or O27.

Bob Nelson

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Posted by Anonymous on Monday, November 29, 2004 9:53 AM
Hey Ya'll

You will definatly want to go with 0-72 or Wider (K-Line conveintly makes larger curves in tubular, and grargaves in the Hi-Railing area)

Even though I am 13, since it was my idea, we have gotten a group of O scalers (3 rail), to build a large sprawling realistic Hi-Rail layout in the recently restored train depot in Myrtle Beach.

We are going to use the large freight area on one side of the depot (this is the biggest non-separated by walls place in the depot. There is another area for tickets and a waiting room togeather).

We have come up with a good many scenes such as a mountain range where all this comes in. The mountain will be built from the floor up, like one in a movie from TM that Micheal Premak had on his layout.

How ever, we will build several mountains so the visitors can walk thought the mountains and see the trains from inside the layout, not just outside.

We have planned to use a 2% grade and we are going to use 0-27 and larger (if we need a larger radius then what is factory made, flex track will figure promintly on the layout. We will partner with Creative Pastime Hobby shop in Conway, who will donate track and sceanery.

After we build this, we will partner wth the Carolina Southern Railroad (They own the all the track at the depot) to restore several of there passenger cars and put them on display at the depot to turn it into a railroad meuseum.

By the way, this railroad runs from Myrtle Beach SC to Conway SC, this branc is hardly ever used, and from Conway, it goes through Loris and Tabor City and then to Chadbourn, NC.

In Chadbourn, it spilts off in two directions. One way goes to Whiteville, NC and the other way goes to Mullins SC, where it interchanges with the CSX railroad.

This railroad is run off of first generation locomotives and has 10 old passenger cars, and 3 unuseud E8 A units and several unused F- units as wells as some unused geeps and sd's. They have 11 locomotives in operation.

I hope I helped
Nick
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Posted by Big_Boy_4005 on Monday, November 29, 2004 1:46 AM
Boyd, that sounds nice, but it doesn't work that way. The diameter of the circle and the height needed between levels is what determines the grade percent. In your case with 6" rise between levels, and a 42" diameter circle, your grade will be about 4.5%.

Remember my helix? I was gaining 8" per turn, but that is 10 feet in diameter, and that is a 2% grade.

If you can't make a bigger circle, could you make an oval? Anything to lengthen the run, that's what will bring the percent down, which, at 4.5% is about the max.
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Posted by daan on Monday, November 29, 2004 12:58 AM
Boyd, I doubt if you can get down to 2% grade with 042.. I don't know exactly how it is calculated, but you have to rise 6 inches in the amount of track in a 042 circle. A 2% grade is a very gentle hill, so about every train should work with that.
Daan. I'm Dutch, but only by country...
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2% grade, 42" circle questions
Posted by Boyd on Sunday, November 28, 2004 11:48 PM
I might run a loop into and out of a small closet. The circle would have to be 42" max. I'm planning on a 2% grade. What kind of trains would handle this? Every thing I have can run a 42" circle. If I weren't renting I would have cut a hole in the wall long time ago to put in a 72" circle track.

Modeling the "Fargo Area Rapid Transit" in O scale 3 rail.

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