Question for route builders, Track Profile Data?

My good buddy Eric sent me the track profile chart on the route i'm building last night. My question is this... It lists the grade changes between every mile marker on the branch, so how would I encorporate that into MSTS? I know there is a way to make mileposts show up on the track monitor, but can that be used in the route editor also? Any feedback would be greatly appreciated. Thanx
(Wp713) S.L.W.
SP Ione Branch (circa 1980)

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Question for route builders, Track Profile Data? [View All], wp713, 09:23 AM, Jul-31-02, (0) RE: Question for route builders, Track Profile Data?, jleslie, Jul-31-02, 07:49 PM, (1) RE: Question for route builders, Track Profile Data?, SP9800, Jul-31-02, 09:51 PM, (4) RE: Question for route builders, Track Profile Data?, jleslie, Jul-31-02, 11:04 PM, (6) RE: Question for route builders, Track Profile Data?, century242, Jul-31-02, 09:23 PM, (2) RE: Question for route builders, Track Profile Data?, landnrailroader, Jul-31-02, 09:29 PM, (3) RE: Question for route builders, Track Profile Data?, DKlemm, Jul-31-02, 11:04 PM, (5) RE: Question for route builders, Track Profile Data?, DRGWK36, Aug-01-02, 11:42 AM, (7) RE: Question for route builders, Track Profile Data?, DKlemm, Aug-01-02, 08:25 PM, (8) RE: Question for route builders, Track Profile Data?, robertreedy, Aug-01-02, 09:39 PM, (9) RE: Question for route builders, Track Profile Data?, DRGWK36, Aug-02-02, 08:29 AM, (10)

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I'm not sure if I understand what you're trying to figure out, but I'll take a stab at it and say you want to be able to convert real life grade data into MSTS.Grade is figured out by the formula:grade = rise/runIn other words, if you rise 10 feet in 1000 feet of run (10/1000) you get .01 which is a 1% grade.You could figure out how to translate that I guess, but you would have to do a lot of converting math. You can figure out the percentage grade for a real piece of track in one mile and use the same percentage on the MSTS track.If this is what you are looking for let me know and I'll help with the formulas if you can't figure it out.Jeff Leslie

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Ever since a lengthy discussion in the MSTS chat room, I have always wondered how a grade is measured. I know one of the parts of the fraction is the vertical rise. However, I am not sure how "run" is measured. Is it the horizontal distance, or is it the distance traveled along the track? If it is horizontal distance, then a 45-degree angle forms a 100% grade. If it is the distance traveled on the track, then a 90-degree angle forms a 100% grade. You can see that as the angle's measure increases, the difference between the two different grade expressions increases as well.

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Ok, I'll re-phrase it....grade = vertical rise/horizontal distance (run)This is the method I use at my job to calculate slope for roads.You are correct that a 45 degree angle is 100% grade. In other words, 100% grade means you are gaining altitude at the same rate that you are travelling horizontally. A way of imagining that would be a rise of 100 feet in 100 feet of horizontal distance as an example. If you go steeper, lets say you rise 100 feet in 50 feet of horizontal distance, then you have a 200% grade. A 90 degree vertical angle is technically not a grade because you would have "0" as a horizontal run, which would give you 0% grade. A 90 degree vertical angle is a wall not a slope. Angles like that don't exist in railroads though, unless you are talking about one of those crazy Alpine tram routes that climb up the side of the Swiss Alps.I did some experimenting with this a while back in MSTS, and I don't have all the data here, but I can give you an idea of how to do it off the top of my head.When you lay a piece of track you will see a "y" value which is vertical distance. That is not the same as Altitude. The vertical distance is in meters above sea level I believe, which is matched to your DEM data. As long as you measure your vertical distance in meters and your horizontal run in meters then you don't have to convert. If you use 5280 feet as a horizontal run then you have to either convert the mile to metric or the metric to US.You have a given piece of track with a "y" value. If your slope is constant for a scale mile, lets say you laid all the track for a mile with -.300 elevation for the whole mile, you can take the "y" value at the end of that mile and get the exact slope for the track in that mile. If your slope is not constant, then the overall grade will be accurate for the mile but it won't be a true representation of the track within that mile because you can have varying slope within that mile. I'm not sure but I believe railroad grades are represented as both maximum grade and average grade in a given horizontal distance.I hope I haven't confused you all here because I think I just confused the hell out of myself....=)Jeff Leslie

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I took delivery of the Western Region Track Profiles booklet for the Espee few a week or so ago. Bought it on Ebay for about $20.00. It goes from Portland south to Sacramento, Sacramento east to Ogden, Sacramento south to LA and L.A. east to El Paso. It has the Tillamook Branch, Coos Bay branch, Siskiyou Line, Mina Branch, The NWP, Santa Cruz branch and the Calexico Branch just to name a few."Keep on Trucking by Train"
"Your freight goes great with Great Northern."Erik Pierson
Sacramento, Ca
www.sacramentolocomotiveworks.comBringing the steam engine to the digital age.

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The explanation given for computing percent of grade, or what percent means is correct, but the rest of the comments will get you in trouble. When you elevate one end of a piece of track to make a grade, you are not increasing it by the % of grade, but rather by a function of the angle of the grade. Look through the file library. One of the early designers produced a chart of the grade angles to use and he put the % of grade in one column, and the related angle in another. He called it "Gradient.txt" and Stuart Thurston (Weevil) is his name. Search on those values.However, for example:An elevation ANGLE of .05 is equivalent to a grade of .09%. On my Blue Ridge Sub. of CSX rendition, the grade on the "Loops" area averages 1.1%. A gradient of 1.05% equates on an angle of .6. The maximum grade on the recently uploaded Raton Pass line is 3.5% which roughly translates to a elevation value of 2.1. The relationship is not linear.On another point. An actual profile may show many changes in grade, largely to compensate for degree of curve. This is virtually impossible to duplicate in MSTS, so if the grade did not vary much over one mile, I just used average over the whole mile. I did not break miles into smaller pieces than .5 mile.While on the subject of degree of curve. Railroad curves are measured in degrees, but MSTS requires us to use the radius. If you take 1746 and divide it by the degree of curve, you will get a good approximation of the radius in meters. Thus a 10 degree curve would have a radius of 174.6 meters (175 for practical purposes). For this reason, one uses a lot of dynamic track to get a route as close as possible to the real thing.J. H. Sullivan, P.E. (retired from Engr. Dept. of CSX)

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WP713;Here is what I do and there probably is an easier way, but heck it works for me! I have a spreadsheet that converts feet to meters since my track plans list feet and MSTS uses meters. I have that printed out. I then take my start point to the correct beginning elevation and work towards the next mile marker by doing some math. I take the meter height of the next mile marker minus my starting point. I figure each mile is about 16 100 meter sections so if I need to rise 3.5 meters, I divide 3.5/16 equals .21875 rise per 100 meters. Then as I lay track I look at where I need to be every 400 meters to make sure I'm rising/declining enough.

David Klemm
Illinos & St Louis Divisions
IC Version 1.0 uploaded

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The grade changes at the mileposts will tell you what the changes are between two mileposts, but there can also be a lot of changes in between, especially for route in hilly or mountainous country. The narrow guage routes, for instance, often did relatively little grade work during construction, and pretty much laid the track right on the ground as they found it whenever possible. So there may be ups and downs in the course of a mile that shows little or no grade overall.If I recall, someone had uploaded a spreadsheet or table that converted the elevation values in the MSTS placement tool to the corresponding grade. So that way you can look at a piece of track you're laying down and see what the grade is for that specific section. Check out the Utilities or Misc. sections in the file library.Andy

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Andy;If the comment about grade changes between milepost was in reference to my comments, I wasn't clear. What I gave was an example. Of course going from my starting point I go to the next transistion point, up or down, or milepost which ever comes first. Using the same 1600 rule I then figure how far I need to go and do the math. Hope that is clearer.

David Klemm
Illinos & St Louis Divisions
IC Version 1.0 uploaded

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Andy is this what you were talking about"RE: MSTS Gradients"
The elevation listed in TS is in degrees, which I personally found a little confusing . After some questions, the upshot is, to convert to (as we Aussies and you Brits use the gradient ratio,) it is 1 / sine of the angle degree of gradient, or the sine of the angle x 100 if you want the gradient percentage.... Here is one I prepared earlier (approximate to no decimals)
Degrees .............Gradient %........... Ratio
0.150..................0.26..................1.381
0.300..................0.52..................1.190
0.450..................0.78..................1.127
0.600..................1.04..................1.95
0.750..................1.30..................1.76
0.900..................1.57..................1.63
1.050..................1.83..................1.54
1.300..................2.20..................1.44
1.450..................2.50..................1.39
1.600..................2.80..................1.36
1.750..................3.05..................1.33
1.900..................3.31..................1.30
2.050..................3.57..................1.28
2.300..................4.00..................1.25
2.450..................4.27..................1.23
2.600..................4.53..................1.22
2.750..................4.79..................1.21
2.900..................5.06..................1.20
3.000..................5.23..................1.19
As you can see, what was initially taken as a gradient percentage, say 3.00 (which is not too bad - 1:33, actually equates to greater that 1:19, strictly Shay and mountain goat country...
Cheers,
OZ
RobertR

RobertR .. ADF-M&RM at http://www.adfrr.com

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LAST EDITED ON Aug-02-02 AT 08:30 AM (EDT)

David - I think I understood what you were saying, but then again, I think that a lot (to my later regret - ). I was only pointing out to other folks who might read this thread that the gradient doesn't have to be constant for a full mile. I think your approach is a good one - it doesn't get too complicated with the calculations. It would be nice if the RE could display that value (grade) rather than the degrees, but there's a LOT of things I'd like to see in the RE before they focus on that. I also wanted to point out that some routes are not going to have very well prepared grades, especially the low traffic lines, and it's mostly a matter of following the terrain. That's pretty much the approach I took with CTSRR - the builders of the actual line did as little grade work as possible, so my approach was to point toward the next marker, put my track segment down, and rotate it until it was touching down on the far end. If the grade was too much, I'd make some adjustments, but for the most part the track was where it was. That makes for a bumpy ride and a train that can be tricky to drive, but I guess that's half the fun with the game.Robert - that's exactly what I was referring to. I wasn't aware of the difference of measurements in Europe, though. Another bit of information that my wife thinks is taking up what could be useful space in my head.Andy

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