# Grading on a Curve?



## BillBrakeman (Jan 3, 2008)

I wish to build a grade on track that includes a curve. How do I keep the grade even on the curve?

Bill


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## Totalwrecker (Feb 26, 2009)

Working on the ground fooled my eye. I'd step way back and using a scale 4x4, I'd eyeball the track line along the stick.
I gave up on my advanced trickery and bought a digital level at Sears. I got the short one and use a longer straight edge as a base when needed. It's also good for cross elevation.
It reads out in % which helps my old sporadic figgure-outer. Oh boy it revealed a lot of roller coasting!
If I remember correctly, it was under $40
John


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## Semper Vaporo (Jan 2, 2008)

The most universal method to fit just about any arbitrary curve, regardless of construction method, would be to attach a small block to one end of a carpenter's level such that the bubble is centered when the level is on the desired grade. Then as you build the sub-roadbed you can slide the level along in increments to check for a centered bubble.

There are other methods that would depend on the degree of curvature, the length of the curve and the length of the overall grade, as well as how the track support is being built (flat on the ground with nothing but ballast, or on a trench with a packed subgrade roadbed material, or on something like a ladder roadbed with the dirt mounded to the sides). Each situation might present a simpler method whereas some methods for one situation might be too complicated for other situations.

Curves are like a grade and require more power to negotiate just the same as a grade does, thus I recommend that you lower the grade in the curve itself. That will cause the non-curve portion (if any) to be a higher grade to make up for it, or if you can, lengthen the curve to get the same elevation change with a lower grade percentage. It all kind of depends on the landscape the curve and grade are having to fit.


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## kormsen (Oct 27, 2009)

my trial and error investigations showed, that an R1 curve equals 2% of grade (more or less)
so if you plan to make a 2% grade, the curved part should be level.
but if you have short trains and strong locos, that you plan a - let's say - 5% grade, the curve should be no more than 3%.


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## John J (Dec 29, 2007)

One thing you might try is using some kind of form. Like the flexible garden edging. Set the form so you have the grade you want then back fill to it. Fill in between the forms with what every you are going to use for road bed. When everything is to your liking and solid You can gently pull the forms out or bury them and let them hold everything together. 

JJ


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## Skeeterweazel (Feb 11, 2014)

I'm using both small shim on a level like Semper Vaporo suggested and a water level. Using long tube, about 20' that goes into a container w/ about 2 gals of water (using plastic container that kitty litter came in). Keep container centralized on layout then can walk around and measure grade w/ tube fixed to yardstick. Have to calculate rise-over-run to get your grade. If interested in water level there are videos on Youtube. I would suggest the container method rather than using 2 yardsticks. Not a perfect way to do it but error is very small.


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## John J (Dec 29, 2007)

At one time I had a rotating Laser beam. I mounted it on a concrete pedestal.

I covered it with a 5 gal bucket when not in use. That was my Zero reference.

I use to measure up and down from there. Once I got the basic layout down I abandon that. But it was a big help

You might want to put one end of you water level in one spot. Then do everything off of it. 

JJ 

JJ


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