11-30-2012, 03:00 AM
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
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
Fake It till you Make It, then Fake It some More