Elevation Changes

First impression I get is...

We might need a diagram of the room and layout, as there is a bit much to juggle envisioning how everything is laid out. But that's just my impression at 5:30am

Second impression is that degrees of elevation is (maybe?) an obscure measurement in the model-train field. We generally express grades in terms of percent, defined as the number of vertical feet per 100' of horizontal distance (25" in O-Gauge).

Under this model, a 3% grade would rise 3/4" over a horizontal distance of 25". The typical Lionel trestle set produces a grade of 6% with 0-27 sectional track, and slightly less using the longer 'O' sections.

Not that any of this directly addresses your issue, but it may make it easier to clarify your situation going forward.

Well, other than the suggestion that you can start your grade with a less steep section (to prevent your longer locomotives from shorting out on the center rail) then increase the grade at the point that the locomotive pilots resume a normal distance above the railheads. Such a practice is known as an easement.

---PCJ

Ken, a 6" rise over 18' is about a 3% grade. (6" divided by 216").  A 12" rise over 18' is about a 5-1/2% grade.

Your problem is not really with how steep your incline is (although 5.5% is pushing it); the problem as you describe it is with your transition.  You cannot go from dead level to 5.5% or even 3% incline in one track section.  Your problem will not only be cowcatchers hitting the center rail; you will have wheels coming off the track as trains try to bridge that transition as well.

Add a couple of feet at the bottom end of your incline, and use it to gradually ease into the slope; make the first track section 1% or less, the second maybe 1-1/2%, and so on.

Same thing at the top, gradually ease back to level over several track sections.

david

Hi Ken,

I don't think that you have problem visually with the rise & elevated track passing over the RH\TT area. Check out Eric's Trains videos of his layout.

The slope with a 18' run to 6" is rise/run=slope  6"/216"=2.7° slope. If you only have half of that or 9' to rise and 9' to descent it would be 6"/108"=5.5° slope.

It would be better to work with 6.5" or 7" to allow for the height of the lower railhead(usually around 11/16"+roadbed).

Your grade slope should result as manageable.

I have seen basswood used to create the transition from level to the start point of the grade to keep the pilot from hitting the rail. Adjust a few pieces of track before the start with varying thicknesses.

You can get a specific answer and better assistance if you can post your working track plan and tell us what trestles you will use.

Edit: the 18' run to the 12" outside perimeter would be 12"/216"=5.5° slope

Carl, your math is good but you are still expressing it in degrees which as RailRide pointed out, is not true.  The track is not at an angle of 5.5 degrees from the level.  

The number 5.5 is arrived at by dividing 12 by 216, which comes out to .055, which is 5.5%.  Stated another way, 12 is 5.5 percent of 216.  

Rise over run is a percentage, not the degree of the angle.  It's a common misunderstanding.  You can measure the degree of that angle from level, but it is not 5.5.  In fact, a 5.5% slope is almost exactly a 3.0 degree angle from level.

hope this helps.

david

Thank you all for your comments and help. The one thing I am aware of is that the slope is just the tangent of the angle, so once you have the rise/run you could take the arc-tangent to get the angle.

I have attached a very rough sketch of my layout. The only thing cast in concrete is the engine house/turntable location and you can see the problem. The is a yard-level track that goes around the engine house and there is no room for another track unless it is above the yard-level track. I hope the crumby sketch helps a little.

I think hojack's suggestion hit the nail on the head. My biggest concern was the transition points. Hojack, can I assume that I should keep the slopes gradual all the way to the 12" elevation point for the same reason (once I have cleared the 6" point I still have another 6" to climb)?

A tangent is a line which touches a curved line or arc at a single point, but does not intersect it. It doesn't really apply here because we aren't working with an arc.  Your layout starts on a flat surface, not a sphere.

You have your track on the level, and then the track wants to slope up from that level.  You're really just looking at an angle between two lines.  The slope of the line can be measured as a percentage of rise over run; or the angle created can be measured in degrees; either is okay, just understand the difference so that the layout doesn't get jumbled in the confusion.

In practical terms, what you have discovered is that if the angle at which the sloped track starts to rise from the level is too acute, it will cause problems for the trains.  So all you need to do is make the angle less "sharp"; more gradual; as has been mentioned, you want to "ease" the transition where the slope starts up from the level.

So, using several short track sections, you make a series of small angles, rather than one sharper (acute) angle, each of which gradually increases the slope of the track.

So instead of this:

You want this:

Which may look like a curve, but is actually several very small (eased) angles between straight pieces of track.

But I am not clear what you mean by saying,

"can I assume that I should keep the slopes gradual all the way to the 12" elevation point for the same reason":

You only need to gradually increase the slope in the initial transition. As you gradually ease each track section a little steeper, you will reach a point (in maybe 3-4 track sections?) where your track is now sloping up at the desired pitch (5.5% slope, or whatever it is that you need to gain the desired height in the available space).  After that, the slope is what it is: there is no need to continue getting steeper.  

david

hojack,

Yep, I see the difference. I've used the slope in inches in most of my practical applications. I never had much need for the angle.

ken,

Will you build the ramp like a U shape?

Rising to 6" in 23' or 24' will keep the slope slightly under 3% and the run from the transition point at ~19.5' to the 12" height will be around 3%. 

Hojacks recommendation for the gradual rise to the first sloped track will keep low pilots on steamers from hitting the center rail. 

These slopes don't appear that they would cause a problem with magnetraction or traction tired engines.

Hi David,

Second part makes sense. First part is a misunderstanding. Rise over run is the same as height divided by length in a right triangle. The angle made by that rise over the length can be computed by taking the result of the division as the tangent of the angle. Using the arc-tangent of that result provides the angle in degrees (in a right triangle the side opposite the base divided by the base is the tangent). Your illustration of the sphere is another description of a tangent condition.

Enough of the Trigonometry. Since I left room on all sides of the yard track (except at the end past the engine house), I could make the ramp longer with a slope of about 1.8%. However, that said, I still like your idea of increasing the slope off of each slope in steps.

As to my question about coming off the slope to go level at 12". If my slope at that point is steep, I assume I can't just flatten out at 12". So don't I have to gradually slope up and then gradually slope back down to reach level at 12" with again a shallow slope??

If I understand all this and my assumptions are correct, it seems that to build that ramp might be kind of complicated. Anyone have any designs??

Ken

Moonman,

In response to your question, yes I could actually make the ramp almost a full rectangle since I left room around the yard-level track to put the ramp (except on the engine house end). If I stretch the ramp to 55 feet, I still have a slope of about 1.8%, and that may be too much at the transitions. I will run some tests with 2, 3-foot track sections.

Ken

Ken,

here's some concept photos of your layout plan. I used Gargraves track and Ross switches. 054 is your maximum radius. I used a curved switch to transition to the ramp.

Layout height is 36". wall shelf is 48". Walkway is 24".

Issue #1 How to reverse direction after coming back down from shelf

Issue #2 reposition wye to fit curve on the left side.

The wye gets you on and off the shelf. You'll have to duck under. It's at 47 3/4" height.

The shelf will need corner triangles to fill in. You can use 054 on a 12" wide shelf.

I think a reverse loop on the main level will address the direction return to clockwise to enable travel to the ramp again.

There's only a few flex pieces and one cut piece of track. The rest of it is sectional.

I used SCARM, if you want the files to work on the design.

Here is my take on modeling vertical easements.  First off, here is a diagram I found a while back:

The transition from level to grade (up or down) needs to be gradual to avoid cars uncoupling and steam engine pilots and snowplows touching the track.  One solution you see in layout books is to use plywood subroadbed. When one end is raised, and the other held level, the plywood will naturally curve gently to meet the grade, forming an easement (ensure it has no joint near the change from level to grade).  If this is not as smooth as you want, you can vary the sharpness by adding risers along the curve to fix it in a given shape. Build it, then test with appropriate trains before adding scenery.

In the photos below, you can see how the builder used a solid sheet of plywood for this small layout and cut the plywood to form the grades.  Even though the plywood is at different levels, it is still a single connected sheet.

I plan to use strips of 1/2" plywood as my grade subroadbed and will bend it the same way to have a gradual transition.  Hope to have pictures soon.

Carl & Ron,

Thank you both for the suggestions & illustrations/pics. Carl I really like your wye and the way you have shown it fits perfectly with my current configuration.

Although nothing is done on the top level, I will take a couple of pics to show you what I have. I'm going to have to go back to my Trigonometry to figure out how to partition the slope 'steps'.

Ken

On the first piece of track for the grade , a 37" straight, it rises from 36.02 to 37.11. That's not steep enough for a steamer pilot to hit.

I am not sure how to move the wye more to the center to leave room for the curves.

I assumed that there would be a bridge at the entrance or opening.

I did come up with a crossover on the main level for reversing direction. Not sure how that would interfere with the rest of what you had in mind. used 072 switches and curves to keep it flowing. It can move up or down to situate it.

OK, here are some pics of my layout and another rough sketch of what I believe the ramp would look like.

I tried to show the place where the layout crosses (up) to the outside level from the yard. I also tried to show the spaces I have left all the way around for the ramp on the outside of the yard tracks, except where that track goes behind the engine house (also shown).

I have made a sketch of what the ramp might look like and attached that also. My sketch is greatly exaggerated, but the principle (if I understand what you all have suggested) is there. The base of the ramp only needs to be strong enough to support the heaviest engine without flexing a lot. It then would seem that the segments or steps would have to be held together by side panels on each side of the base. I am not sure if the supports should go in the middle of each step or near the junction points.

Any comments, suggestions would be greatly appreciated.

Ken

I see now. You already have the reversing tracks that service the accessories. Ok the ramp.

Take a look at how Alex did it for the Hidden Pass Junction. March 27, 2011 post. he cut the ramp or elevation supports with the percent grade converted to degrees for the bevel. Then he cut quiet brace in the outline of the track(slightly wider) for the roadbed.

You can cut the roadbed out of 1/2" ply. Lots of great tips and techniques in his thread.

I see them spaced between your switch motors running around the edge of the layout. So, the 2.9% up to the RH is 1.66° and the run to the shelf from the RH is 2.5% or 1.43°.  Need a table saw or miter saw to make those.

Slope percent to angle degree calculator

http://www.calcunation.com/cal...e=Convert+to+Degrees

Sorry,

If you make the blocks, they can be screwed from the bottom or toe nailed (screwed )from the top.

Carl,

I just finished looking at the pics and stopped after the video from the Hidden Pass Junction link. That is mind-boggling. I am now ashamed to continue with my puny endeavor. His method for doing the elevation changes is great. Only problem I might have is that my base is 1/2" plywood covered with 1/2" inch homasote. I don't know what the homasote will do if I screw into the supports from below. To pull the supports tight might crush the homasote. I'll have to do some more experimenting, unless someone else has already done this.

Thanks so much Carl.

Ken

Well, I have thought about what you have advised and shown. I did some simple measurements and ran the numbers. My 1st measurement indicated that 3/4" rise in 40" would give me good clearance on the engines. But that's a 1.07 deg angle which requires a 57.7 ft. run to get to 12.5" (say 13"). That's more than the entire perimeter of my yard.

If I increase the slope to 3/4" in 36" (1.19 deg), I get to 7.5" at the engine house with a 30 ft. run, and with 23 ft. remaining to the next level, I get to 13.22".

This all assumes a constant slope throughout. By decreasing the slope to 1.09 deg. and increasing the slope in 2-foot steps, I can shorten all the distances, but then I have to make the ramp as I have shown it in my previous sketch (and I'm still not sure how to make that ramp).

Ken

I don't understand all of the math worries. They are toy trains. Ingenerio 1(Alex) runs scale engines and used a 2° slope. The constant slope from the straight at the opposite end to get to 6" over the roundhouse, is the 2.9% or 1.66° climb in my ship photo showing the transition point at the engine house. Certainly acceptable for all but 2-rail scale engines. Why is it now 7.5" at the engine house?

The supports only have to be snug. They can be tightened enough before crushing homosote.

Lay the track on a 4' x 8' piece of 1/2" 7-ply plywood. Scribe the lines around the outline of the track about a 1/2" wider. Jigsaw the piece out. Then do the next section. If you use 1" x 4" (nominal size is smaller) for the supports you would be able to walk on it. Paint the supports a concrete color.

You could also build a pylon with 1" x 4" blocks and a 1" dowel for a support. Getting the bevel of the slope on the top edge is the key with either style.

The other method to access the shelf level is a helix. That is out because you don't have the space. It would need about 45" square using 042 and would result in a steeper slope to maintain clearance.

Put some track together and mock it up, supporting the track with whatever you have around. You'll see the transition and the climb are acceptable.

Carl, again not to belabor the point, but I have 3 issues. First, I must get to 6" at the engine house. Then I must get to 12 to 13" by the upper level point. Most importantly, to run all engines, I must keep the slope shallow enough as to not hit the cow-catcher. So I chose a slope that met all criteria in a constant slope ramp (which got to 13.22" at the end and 7.5" at the engine house). I could do the step thing, but not sure how to make it. The reason for going up to 13", is to allow me to get back to level as I cross to the upper elevation area.

Ken