Help with nolix (modified helix)

[rsn48]

I took this topic to another forum but got limited response so hoping some here have some great imput.

I'm building an N scale layout but I know more in HO have build RR's with inclines (grade) than in N scale. And a grade is a grade is a grade, a 2 % percent grade in HO is the same as a 2 % grade prototypically.

What I am building is a modified helix as you'll see in the pic below. I really have three questions but I'm open to any comments that will help me. In the nolix area as you will, the trains will be going four times around the area, in the front "S" area, the train will be visible twice in a four rotation. The first and second time (visible the second time in the S area), the track will be stack one above the other with the first time not visible. The train will come around a third time and be visible, seperated by a river (Fraser Canyon). The fourth time the track will not be visible.

Question one: Without using foam, I'm using plywood roadbed 1/2 thick supported roughly every foot, how do I begin the first two feet of the grade to make it gradual? I'm planning roughly on a 2% grade, a wee bit more actually.

Question two: If I am making a 2.2 % grade, then .2 would be roughly 3.2 16ths of an inch. How finely can you measure this minutely in building a 2.2 grade.


Question three: How do I compute the grade or rise in the S section, since it isn't straight, can I just fudge and set the grade a tad higher than 2.2 in this area (since it is easier for the train to snake its way up a grade then directly up a grade).

[BR60103]

The best way for the start of the grade (well one good way) is to get a 4-foot length of roadbed and tack down the first foot on the flat and then tack the last foot to the 2.2% grade. This makes a natural bend.

Another is a form of "spline". Cut thin boards to the profile desired with a curve. Then glue them together to the thickness you need. I don't know what curve should be used -- I favour something 5 feet or over or 2 metres. This may take a bit of math.

Not sure about the S curve area. Curves put more drag on. There will be more track length along the curvy bit than a straight line. The grade will also translate into cant (tilt) across the track in some places and much of it will be the wrong way.

[Mr Fixit]

In both the real and hobby world curvature in a grade increases the rolling resistance that a train and in particular a locomotive must work against, which is why Engineers of the Civil variety not the Locomotive kind, talk about compensated grades.

A compensated grade may be listed as 2% for example, when in actual fact it is less than 2% due to being 'compensated' to take into account the rolling resistance due to the curvature.

I would like to suggest that you do some mock-ups of different grades and different sizes curve radius close to what you will be using in the finished location.

You will also need to consider the performance of different locomotives [steam vs early diesel vs modern six axle diesel] and the lenght and make up of the trains you will be running freight vs passenger.

Also be aware of overhang and under cut of equipment and the required clearances. Vertical clearance of equipment and you the operator?

How about derailments and track maintenance? How will you get your 1:1 scale body, hands and eyes in to attend to the helix arrangement.

You will also need to consider vertical and horizontal easements to your curves to make life easier for your locomotives and to prevent the 'toy train look' of a train lurching into a curve.

This is just a summary of some of the articles I have read in Model Railroader and Model Railroad Planning over the years.

Helixes have brought many a model railroader unstuck over the years and caused many a headache, so be prepared for plenty of and this as you tackle this task.

Mark

PS Best Wishes

[ratled]

A good way to consider for starting your gradual grade with plywood would be the cookie cutter method of benchwork. It will give you no bumps at the transition and allow for an easment grade before your 2.2%.

As for the S area, just find the elevation points at key points and regular intervals. Build these to those heights and the grade will have to follow. You can see what I mean as on this fine Nolix RR <!-- m --><a class="postlink" href="http://www.cmrailroad.com/Layout.html">http://www.cmrailroad.com/Layout.html</a><!-- m --> . This should solve Q 1& 2. Be sure to have one good benchmark and think about using a story board or witness board

Off hand, your area looks too small for a nolix but that just could be me and no longer familiar with N Scale

ratled

[rsn48]

My buddy and I are doing some mock ups with cardboard of the tall mountain that will be going on and up from the S curve tonight. In another forum it was suggested you can download an app for your android phone for levelling (it can be calibrated), which I have done and to my amazement the sucker seems to work.

I'm working in N scale so over hang, etc isn't quite as critical as in the larger scale. My road bed will be 2 1/2" wide even though there is only going to be one track quite close to the wall so if there is a derail there will be some rescue room. Also I'm planning some kind of foam lip to prevent spillage. But you can't tell from the picture, there is a nice soft pile rug on the floor; this room is on the second floor of the house that has no basement.

So far I've copied and printed out the suggestions here and in the other forum, so far everyone has been helpful.

Here is the link to the Android free leveling app, also includes gradient.

<!-- m --><a class="postlink" href="https://play.google.com/store/apps/details?id=net.androgames.level&hl=en">https://play.google.com/store/apps/deta ... evel&hl=en</a><!-- m -->