Setting a Gradient

Hi,

I have a hill that is 88m high, and the lowest point is 16.74m. I have laid the track around the hill from top to bottom, it follows the contour of the hill, so I would like to set the gradient.

Now do I have to set the splines to a common height to do this? Also I seem to have trouble finding where on the track to click to set the gradient!

Any help much appreciated!!

Steve

It depends whether it is a DEM, or a hand made hill, and how many miles/feet of track is involved

Most gradients should be well under 2%, and most tracks have an, up and down, zig zag, see saw, gradient

A gradient usually doesn't go directly from a -2.00% gradient, right to a +2.00% gradient ... it usually slowly levels off to 0.00%, then up to 0.10%, then 0.25%, then up to 0.50% ... etc ... etc ... and versa' visa', down to -0.50%, then down to -0.25%, then down to -0.10%

First step is to make sure "Fixed Vertex Height" is ticked in Surveyor options.

Second is basic geometry. If you don't have a gradient profile (or even if you do) measure the vertical change over a set distance and calculate the gradient as a percentage (e.g. a rise or fall of 10m in 1000m = 1.0%), enter this in the gradient box in track options and click each section of track just beyond the spline point through the area. Always worth then double checking with the adjacent "Get Gradient" tool to make sure you haven't cludged it.

For a falling grade prefix the value with a - (minus). i.e. -1.0

Gradients are really dead easy and it should take no time at all to "git gud".

Thanks for answering guys, I must be thick, because none of the above seem to work! Just for info its a transDEM map I've made.

I'll try and do it manually for now

Steve

simtrain said:

Hi,

Also I seem to have trouble finding where on the track to click to set the gradient!

Any help much appreciated!!

Steve

Click to expand...

(O is a spline point)
.........Sect 1...............................Sect 2................................Sect 3...............................Sect 4...........................
O----------------------------O-----------------------------O-------------------------------O-------------------------------------O
..........................................A.........................B..........a............................b......................................................

If Get Gradient is selected...
Clicking the track at A or a will show the left to right gradient
Clicking the track at B or b will show the right to left gradient

If you want Sections 2 and 3 to have a 1% incline...
Select Apply Gradient, enter 1 and click at A and again at a
The track should now be level in Section 1; Sections 2 and 3 will be going up; Section 4 will be going down

If you now click Get Gradient; clicking at A or a will show 1; clicking at B or b will show -1

Type in the desired gradient numeral in the box ... then go to the apply gradient button ... Click the mouse just a tad after the first spline point, and it will apply that gradient numeral ... keep on doing that for each track segment all the way up the hill ... You may miss a hidden spline point, that is hard to see ... so you should keep checking your work backwards every so often, that the gradients are all uniform

A 2% grade is very steep ... So try making the grade a 1.75% all the way up the hill ... If the track is too high at the top of the hill, start back all over again and try 1.50% ... etc ... etc ... 1.25%, 1.00%, 0.75%, 0.50%, 0.25%

Most of my PRR mainline is 0.40%, except in the mountains were it is 1.00% or as much as 1.75%

I like to make my gradient suble changes, 0.00, 0.10, 0.25, 0.50, 0.75, 0.00, -0.75, -0.50, -0.25, -0.10, 0.00

There is some info about this topic here --> https://forums.auran.com/trainz/showthread.php?141218-Building-A-Continuous-Grade-Tips-On-How-To

Thanks for the replies, I've sort of used gradient and manual method, now tweaking to get it just right.

Steve