Gradients

Discussion of model railway baseboard design and construction
Hulldude15
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Gradients

Postby Hulldude15 » Thu Aug 27, 2009 5:50 pm

Hi everyone,

My layout is going to have a hill which the track will run up, it will run from flat up a incline then to flat on top of the hill. This results in a bump in the track, as shown below, what would the maximum gradient be to run a train similar to a pendolino.
Image

Then gradient does not need to be realistic, but if anyone has worked it out in OO gauge could you please reply.

Thanks

Hulldude15

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Dead Man's Handle
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Re: Gradients

Postby Dead Man's Handle » Thu Aug 27, 2009 6:49 pm

How long is it (the train similar to a Pendalino)?

1 in 30 would be the absolute maximum you should even bother considering. I'd guess about 1 in 40 would be workable. Hopefully someone will have a more specific answer.

Ade
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Zunnan
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Re: Gradients

Postby Zunnan » Thu Aug 27, 2009 7:21 pm

As dmh says, 1:30 absolute maximum. The shallower the angle you can use the better, and the bump you mention should be eliminated entirely. You'll want a nice smooth transition from level to gradient and back to level, the best way to achieve that is to slot the baseboard where the gradient begins and ends, and bend the trackbed upwards/downwards to the desired angle and fix it in place before linking it with a piece of trackbed set at the maximum gradient for the distance required between the transitions. This should leave you with a nice smooth bend in the track which takes a good few inches to reach the maximum gradient from the point that the incline begins/ends.

HTH

Hulldude15
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Re: Gradients

Postby Hulldude15 » Thu Aug 27, 2009 9:52 pm

Hi Dead Man's Handle,

Well I will be using the pendolino, and I will be buying a similar style train (of which I dont know) for my layout.

Thanks for your help

Hulldude15
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Re: Gradients

Postby Hulldude15 » Thu Aug 27, 2009 9:55 pm

Hi Zunnan,

Don't quite understand you, could you put it a bit simplier??

Thanks

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Zunnan
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Re: Gradients

Postby Zunnan » Thu Aug 27, 2009 10:19 pm

Basically, you don't want the track to go straight from level to gradient and back to level. You want the track to bend upwards gradually into the gradient, then gradually back to the level.

Hulldude15
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Re: Gradients

Postby Hulldude15 » Fri Aug 28, 2009 9:11 am

Ok thanks

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egroeg93
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Re: Gradients

Postby egroeg93 » Fri Aug 28, 2009 4:23 pm

I very recently got a set of elevated track supports, and so far I have set it up at a gradient of about 1 in 25. However this sometimes causes derailment at the point you are indicating, so you should try to make the incline as gentle as possible, and at a gradient of 1 in 30+.

Hulldude15
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Re: Gradients

Postby Hulldude15 » Fri Aug 28, 2009 4:55 pm

Just made the structure, and the only way I could fit the slope in, is only if it is 1:12, and we found a way of reducing the bump at the same time. Only problem is the pendolino wont run up it, Only small trains with 1 or 2 carriages can go up.

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Dead Man's Handle
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Re: Gradients

Postby Dead Man's Handle » Fri Aug 28, 2009 5:16 pm

When I asked how long is it, I meant how many coaches hehe (wasn't thinking clearly). People run Pendolinos with different numbers...

If you're coming up with numbers like 1 in 12 then you're gonna have to come up with a different idea I think...


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Flashbang
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Re: Gradients

Postby Flashbang » Fri Aug 28, 2009 8:56 pm

Hi,
I'm not surprised. 1:12 is for every 12 inches the track length it has risen 1 inch. That's almost an impossible incline for any loco or train to manage!
1:30 is the minimum most locos with carriages or wagons can manage!
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Dad-1
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Re: Gradients

Postby Dad-1 » Fri Aug 28, 2009 10:03 pm

Hello,
You don't stand a chance with a gradient like you've tried. The transition into and out of the climb will extend the distance needed to make a given climb regardless of what you use as the maximum angle.
I played around with some track on a board and a heavy Heljan class 33 could just make this with a few light wagons.

Image

Geoff T
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noel
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Re: Gradients

Postby noel » Sat Aug 29, 2009 4:34 am

+

GREAT ! .... opportunity for running a Banker.

+

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Flashbang
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Re: Gradients

Postby Flashbang » Sat Aug 29, 2009 10:26 am

At 1:12 it wouldn't want a Banking engine, more like a rack and pinion system :D
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Hulldude15
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Re: Gradients

Postby Hulldude15 » Mon Aug 31, 2009 2:53 pm

Will try and reduce it to 1:20, it just means it will have to have a curved slope as well.


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