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Transition from level track to a grade

3.4K views 7 replies 7 participants last post by  D&J Railroad  
#1 ·
I will be using a 2% grade on my HO layout to gain height to cross over another track. Most of my layout will be level. When transitioning from level to the beginning of the 2% grade how does one handle the slight vertical curve in the rails? This seems like a small item but I don't want to screw it up.
 
#4 · (Edited)
Flyboy has it right.

But you must do the gradual elevation at both
bottom and top. Start the upper transition before
reaching your top grade also by allowing the flex
to find it's natural slope. The longer your grade
changes, the smoother the transition.

Note: allow the flex to find it's slope and once
done then build the support for it. A gentle press
on the flex may be helpful.

Don
 
#5 ·
This is an instance when you can let your ballast grains do the work for you. As described by others, let the flex track sag toward the lowest point if you can't create a proper vertical curve from level and on into the grade. (Many of us use cookie-cutter platforms where a thickness, cut to width for the roadbed, of plywood is screwed flat with the base over four-six inches, and then you screw the far end onto the steady portion of the grade, usually atop a riser cut and positioned to the right height to support the top end of the roadbed.)

The flex will sag, and you can fill part of that gap with door frame shims, and then fill it up to the ties with more ballast grains that normal. Once you glue it, the tracks will be well supported along the vertical curve, just like the prototype.
 
#6 ·
You can also use a section of 1% grade which is about 3" longer than the longest piece of equipment that will use it.

The flex track method gives a smoother curve and is more elegant, but the above method works.
 
#8 ·
As for building the subroad bed to provide that smooth transition from flat to incline, you might consider cutting your roadbed from plywood. The thicker the better. When you bend it up for the grade, the bend of the wood will take a natural transitional bend.