How come?

[kcj207]

Setting gradients accurately on a 2010 Trainz rail bed has me baffled. Having read the manual and explored the forum for subject relative material, the matter remains unresolved. Is it my understanding of the problem or the gradient tool at issue? Any insights from fellow surveyors would be GREATLY appreciated.
If this conversion is correct
grade ratio to % grade = 100/ grade ratio or grade expressed in %
e.g 1:250 grade ratio = 100/250 or 0.4 %grade
then for a 1000 foot length of track with a 1:250 grade, the far end vertex should be 4 feet above the starting elevation [i.e. 1000 x .004 (0.4%) or 4 feet. However, entering 1.250 in the gradient window, and then pressing the Apply Gradient `K` button, produces an elevation of 3.8 feet at the far end vertex; a 5% error.
If one inputs 4 feet and uses the Apply Vertex Height button, on a 1000 foot piece of track, then presses the Get Gradient `J` button, the result is a ratio of 1.32??
If one inputs a ratio of 1.32 and presses the Apply Gradient `K` button on the track, the vertex elevation becomes 3.99 feet, very close to the vertex height expected for a 1.250 ratio.

Utilizing the gradient tool with a 1.100 ratio produces a track bed that locomotives are unable to negotiate with any meaningful load
Does anyone understand what I am doing wrong?
regards

 

[Dermmy]

Basic math issue: 1 in 250 is not 100/250 it is 1/250, the result is not 1.25% but 0.4%. 0.4 is the number to enter in the 'Apply Grade' tool...

 

[kcj207]

Ok Derrmy, thank you for the response...I agree it's something about the math but you will agree that 1:250 = 0.4%. If this number (.4) is then entered into the gradient tool and then applied to a 1000 foot length of track, the far end vertex measured with the Vertex height tool produces the number 1.21 ???? There is definitely something I don't understand about the tool ....what does 1.21 have to do with the ratio of 1 foot elevation for every 250 feet of track or a 0.4% grade or slope??

Has anyone applied a ratio or % grade number to the gradient tool and then measured the resultant grade change with the Vertex Height tool and received an understandable result ??

 

[Dermmy]

Ok Derrmy, thank you for the response...I agree it's something about the math but you will agree that 1:250 = 0.4%. If this number (.4) is then entered into the gradient tool and then applied to a 1000 foot length of track, the far end vertex measured with the Vertex height tool produces the number 1.21 ???? There is definitely something I don't understand about the tool ....what does 1.21 have to do with the ratio of 1 foot elevation for every 250 feet of track or a 0.4% grade or slope??

Has anyone applied a ratio or % grade number to the gradient tool and then measured the resultant grade change with the Vertex Height tool and received an understandable result ??

Aha - I see your problem! Remember in Trainz elevations are ALWAYS expressed in meters irrespective of whether you select metric or imperial units.

1,000 feet at 0.4% = 4 Feet = 1.21 Meters...

Andy

 

[aodgh0st]

oh wow, i didn't know it was meters! that is very useful information

 

[HiBaller]

The best way to build most anything for (or in) Trainz is to use the Metric system. That way you aren't ambushed like that.

Bill

 

[Approach_Medium]

The best way to build most anything for (or in) Trainz is to use the Metric system. That way you aren't ambushed like that.

Bill

I second that. Despite living in the USA (the only major country not using metric), I always use it in Trainz.
Funny how we still haven't 'got it' here in the US. I was taught the metric system in high school physics (that was a long time ago), and yet we're still using the imperial system.

FW

 

[HiBaller]

I grew up with the Metric system as a teenager. I learned to drive in Germany. I've been able to convert back and forth in my head for years.

I fail to see why the 10 x 10 x 10 relationships is so hard to grasp. From nano-meters to Tera-meters they all divide by 10, 100, 1000, etc.

Bill

 

[Bill69]

I grew up with the Metric system as a teenager. I learned to drive in Germany. I've been able to convert back and forth in my head for years.

I fail to see why the 10 x 10 x 10 relationships is so hard to grasp. From nano-meters to Tera-meters they all divide by 10, 100, 1000, etc.

Bill

I grew up with the imperial system, through school, varsity and trade exams. It is much easier to convert form the imperial system to the metric system than the other way around. So simple, to divide by 10 knock off one zero, divide by 100 knock off two zeros etc. if working with decimals move the decimal point one place to the left to divide by ten. Could not be any more simple.

Cheers,
Bill69

 

[itareus]

I wish I had grown up with the Metric system ! When I first started full time work the UK currency was in Pounds, Shillings and Pence. Not the easiest thing to work with when selling Edmonson card tickets in a busy railway booking office......​

For those who don't remember LSD (or was that £/s/d) here is an explanation (extracts from a website):​

"Before decimalisation on 15 February 1971, there were twenty (20) shillings per pound. The shilling was subdivided into twelve (12) pennies. The penny was further sub-divided into two halfpennies or four farthings (quarter pennies).

2 farthings = 1 halfpenny​

2 halfpence = 1 penny (1d)​

3 pence = 1 thruppence (3d)​

6 pence = 1 sixpence (a 'tanner') (6d)​

12 pence = 1 shilling (a bob) (1s)​

2 shillings = 1 florin ( a 'two bob bit') (2s)​

2 shillings and 6 pence = 1 half crown (2s 6d)​

5 shillings = 1 Crown (5s) ​

A £1 coin was called a Sovereign and was made of gold.

A paper pound often was called a quid​

1 guinea = £1-1s-0d ( £1/1/- ) = one pound and one shilling = 21 shillings or 21/- (which is £1.05 in todays money) - A guinea was considered a more gentlemanly amount than £1. You paid tradesmen, such as a carpenter, in pounds but gentlemen, such as an artist, in guineas."

Was this thread about gradients ?? ​

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​

 

[kcj207]

Andy buddy thank you for putting me back on the tracks.

No wonder the locomotives couldn't pull up an incline!! ( using imperial track distances with the ruler and metric elevations in the tool).

I am building a railway from the 1940's (again) and all track data is imperial. With your tip, its now just a matter of building a conversion spreadsheet to work out the metric numbers to input to the "metric" tools in trainz.

regards

 

[norfolksouthern37]

i never seemed to have a problem with the length measurements or surveyor being in metric, but i think it should change with the selection of units as you do in driver. i work in surveying in real life, so i use metric for US government jobs and similar all the time, and imperial for most local stuff, but one thing that always drove me nuts and i have since removed from jointed rail assets is the fact that things display mass in kg and tonnes... THAT is something we dont use common on the railroad in the US.

 

[Bill69]

Here is a link to an excelent conveter for every thing you can think of.

http://www.digitaldutch.com/unitconverter/speed.htm

Cheers,
Bill69

 

[backyard]

Thanks to President Carter...

...the metric system became a mandate back in the '70's....that may before your time Justin...but Carter, was the first Presidential election I voted for...

The problem here, is that a specific grade is entered into the gradient tool, then relied upon throughout the tracklaying event...

That won't work, because when you enter an integer into the gradient tool, it may take that on further than is needed...you need to find the actual elevation above sea level, then adjust the apply gradient tool as needed.